Introduce namespace `langutil` in liblangutil directory.

Also:
- Use {}-style list initialisation for SourceLocation construction
- Introduce new system includes
- Changes the API of the Scanner to take source as value (with move) as opposed to as a reference

118 files changed, 476 insertions, 287 deletions

diff --git a/libevmasm/Assembly.cpp b/libevmasm/Assembly.cpp
index e63194a0..d80f97c4 100644
--- a/libevmasm/Assembly.cpp
+++ b/libevmasm/Assembly.cpp
@@ -35,6 +35,7 @@
 using namespace std;
 using namespace dev;
 using namespace dev::eth;
+using namespace langutil;
 
 void Assembly::append(Assembly const& _a)
 {
diff --git a/libevmasm/Assembly.h b/libevmasm/Assembly.h
index e1993082..d846b475 100644
--- a/libevmasm/Assembly.h
+++ b/libevmasm/Assembly.h
@@ -93,7 +93,7 @@ public:
 	void setDeposit(int _deposit) { m_deposit = _deposit; assertThrow(m_deposit >= 0, InvalidDeposit, ""); }
 
 	/// Changes the source location used for each appended item.
-	void setSourceLocation(SourceLocation const& _location) { m_currentSourceLocation = _location; }
+	void setSourceLocation(langutil::SourceLocation const& _location) { m_currentSourceLocation = _location; }
 
 	/// Assembles the assembly into bytecode. The assembly should not be modified after this call, since the assembled version is cached.
 	LinkerObject const& assemble() const;
@@ -178,7 +178,7 @@ protected:
 
 	int m_deposit = 0;
 
-	SourceLocation m_currentSourceLocation;
+	langutil::SourceLocation m_currentSourceLocation;
 };
 
 inline std::ostream& operator<<(std::ostream& _out, Assembly const& _a)
diff --git a/libevmasm/AssemblyItem.h b/libevmasm/AssemblyItem.h
index 802bde25..a7875171 100644
--- a/libevmasm/AssemblyItem.h
+++ b/libevmasm/AssemblyItem.h
@@ -57,14 +57,14 @@ class AssemblyItem
 public:
 	enum class JumpType { Ordinary, IntoFunction, OutOfFunction };
 
-	AssemblyItem(u256 _push, SourceLocation const& _location = SourceLocation()):
+	AssemblyItem(u256 _push, langutil::SourceLocation const& _location = langutil::SourceLocation()):
 		AssemblyItem(Push, _push, _location) { }
-	AssemblyItem(solidity::Instruction _i, SourceLocation const& _location = SourceLocation()):
+	AssemblyItem(solidity::Instruction _i, langutil::SourceLocation const& _location = langutil::SourceLocation()):
 		m_type(Operation),
 		m_instruction(_i),
 		m_location(_location)
 	{}
-	AssemblyItem(AssemblyItemType _type, u256 _data = 0, SourceLocation const& _location = SourceLocation()):
+	AssemblyItem(AssemblyItemType _type, u256 _data = 0, langutil::SourceLocation const& _location = langutil::SourceLocation()):
 		m_type(_type),
 		m_location(_location)
 	{
@@ -124,8 +124,8 @@ public:
 	/// @returns true if the assembly item can be used in a functional context.
 	bool canBeFunctional() const;
 
-	void setLocation(SourceLocation const& _location) { m_location = _location; }
-	SourceLocation const& location() const { return m_location; }
+	void setLocation(langutil::SourceLocation const& _location) { m_location = _location; }
+	langutil::SourceLocation const& location() const { return m_location; }
 
 	void setJumpType(JumpType _jumpType) { m_jumpType = _jumpType; }
 	JumpType getJumpType() const { return m_jumpType; }
@@ -140,7 +140,7 @@ private:
 	AssemblyItemType m_type;
 	Instruction m_instruction; ///< Only valid if m_type == Operation
 	std::shared_ptr<u256> m_data; ///< Only valid if m_type != Operation
-	SourceLocation m_location;
+	langutil::SourceLocation m_location;
 	JumpType m_jumpType = JumpType::Ordinary;
 	/// Pushed value for operations with data to be determined during assembly stage,
 	/// e.g. PushSubSize, PushTag, PushSub, etc.
diff --git a/libevmasm/CommonSubexpressionEliminator.cpp b/libevmasm/CommonSubexpressionEliminator.cpp
index 04926986..949d2c75 100644
--- a/libevmasm/CommonSubexpressionEliminator.cpp
+++ b/libevmasm/CommonSubexpressionEliminator.cpp
@@ -30,6 +30,7 @@
 using namespace std;
 using namespace dev;
 using namespace dev::eth;
+using namespace langutil;
 
 vector<AssemblyItem> CommonSubexpressionEliminator::getOptimizedItems()
 {
diff --git a/libevmasm/CommonSubexpressionEliminator.h b/libevmasm/CommonSubexpressionEliminator.h
index b20de246..eba25db0 100644
--- a/libevmasm/CommonSubexpressionEliminator.h
+++ b/libevmasm/CommonSubexpressionEliminator.h
@@ -34,6 +34,11 @@
 #include <libevmasm/SemanticInformation.h>
 #include <libevmasm/KnownState.h>
 
+namespace langutil
+{
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace eth
@@ -137,10 +142,10 @@ private:
 	bool removeStackTopIfPossible();
 
 	/// Appends a dup instruction to m_generatedItems to retrieve the element at the given stack position.
-	void appendDup(int _fromPosition, SourceLocation const& _location);
+	void appendDup(int _fromPosition, langutil::SourceLocation const& _location);
 	/// Appends a swap instruction to m_generatedItems to retrieve the element at the given stack position.
 	/// @note this might also remove the last item if it exactly the same swap instruction.
-	void appendOrRemoveSwap(int _fromPosition, SourceLocation const& _location);
+	void appendOrRemoveSwap(int _fromPosition, langutil::SourceLocation const& _location);
 	/// Appends the given assembly item.
 	void appendItem(AssemblyItem const& _item);
 
diff --git a/libevmasm/ControlFlowGraph.cpp b/libevmasm/ControlFlowGraph.cpp
index 86f16d48..d62f5436 100644
--- a/libevmasm/ControlFlowGraph.cpp
+++ b/libevmasm/ControlFlowGraph.cpp
@@ -275,7 +275,7 @@ void ControlFlowGraph::gatherKnowledge()
 			//@todo in the case of JUMPI, add knowledge about the condition to the state
 			// (for both values of the condition)
 			set<u256> tags = state->tagsInExpression(
-				state->stackElement(state->stackHeight(), SourceLocation())
+				state->stackElement(state->stackHeight(), langutil::SourceLocation{})
 			);
 			state->feedItem(m_items.at(pc++));
 
diff --git a/libevmasm/ExpressionClasses.cpp b/libevmasm/ExpressionClasses.cpp
index 42a1819a..abbbbc2c 100644
--- a/libevmasm/ExpressionClasses.cpp
+++ b/libevmasm/ExpressionClasses.cpp
@@ -34,7 +34,7 @@
 using namespace std;
 using namespace dev;
 using namespace dev::eth;
-
+using namespace langutil;
 
 bool ExpressionClasses::Expression::operator<(ExpressionClasses::Expression const& _other) const
 {
diff --git a/libevmasm/ExpressionClasses.h b/libevmasm/ExpressionClasses.h
index df8082f9..a34844c5 100644
--- a/libevmasm/ExpressionClasses.h
+++ b/libevmasm/ExpressionClasses.h
@@ -31,6 +31,11 @@
 #include <memory>
 #include <set>
 
+namespace langutil
+{
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace eth
@@ -82,7 +87,7 @@ public:
 	void forceEqual(Id _id, AssemblyItem const& _item, Ids const& _arguments, bool _copyItem = true);
 
 	/// @returns the id of a new class which is different to all other classes.
-	Id newClass(SourceLocation const& _location);
+	Id newClass(langutil::SourceLocation const& _location);
 
 	/// @returns true if the values of the given classes are known to be different (on every input).
 	/// @note that this function might still return false for some different inputs.
diff --git a/libevmasm/KnownState.cpp b/libevmasm/KnownState.cpp
index b6c1bcc9..a5546e61 100644
--- a/libevmasm/KnownState.cpp
+++ b/libevmasm/KnownState.cpp
@@ -29,6 +29,7 @@
 using namespace std;
 using namespace dev;
 using namespace dev::eth;
+using namespace langutil;
 
 ostream& KnownState::stream(ostream& _out) const
 {
diff --git a/libevmasm/KnownState.h b/libevmasm/KnownState.h
index cd50550e..3ab1c4b1 100644
--- a/libevmasm/KnownState.h
+++ b/libevmasm/KnownState.h
@@ -46,6 +46,11 @@
 #include <libevmasm/ExpressionClasses.h>
 #include <libevmasm/SemanticInformation.h>
 
+namespace langutil
+{
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace eth
@@ -121,9 +126,9 @@ public:
 
 	/// Retrieves the current equivalence class fo the given stack element (or generates a new
 	/// one if it does not exist yet).
-	Id stackElement(int _stackHeight, SourceLocation const& _location);
+	Id stackElement(int _stackHeight, langutil::SourceLocation const& _location);
 	/// @returns the stackElement relative to the current stack height.
-	Id relativeStackElement(int _stackOffset, SourceLocation const& _location = SourceLocation());
+	Id relativeStackElement(int _stackOffset, langutil::SourceLocation const& _location = {});
 
 	/// @returns its set of tags if the given expression class is a known tag union; returns a set
 	/// containing the tag if it is a PushTag expression and the empty set otherwise.
@@ -142,22 +147,22 @@ private:
 	/// Assigns a new equivalence class to the next sequence number of the given stack element.
 	void setStackElement(int _stackHeight, Id _class);
 	/// Swaps the given stack elements in their next sequence number.
-	void swapStackElements(int _stackHeightA, int _stackHeightB, SourceLocation const& _location);
+	void swapStackElements(int _stackHeightA, int _stackHeightB, langutil::SourceLocation const& _location);
 
 	/// Increments the sequence number, deletes all storage information that might be overwritten
 	/// and stores the new value at the given slot.
 	/// @returns the store operation, which might be invalid if storage was not modified
-	StoreOperation storeInStorage(Id _slot, Id _value, SourceLocation const& _location);
+	StoreOperation storeInStorage(Id _slot, Id _value, langutil::SourceLocation const& _location);
 	/// Retrieves the current value at the given slot in storage or creates a new special sload class.
-	Id loadFromStorage(Id _slot, SourceLocation const& _location);
+	Id loadFromStorage(Id _slot, langutil::SourceLocation const& _location);
 	/// Increments the sequence number, deletes all memory information that might be overwritten
 	/// and stores the new value at the given slot.
 	/// @returns the store operation, which might be invalid if memory was not modified
-	StoreOperation storeInMemory(Id _slot, Id _value, SourceLocation const& _location);
+	StoreOperation storeInMemory(Id _slot, Id _value, langutil::SourceLocation const& _location);
 	/// Retrieves the current value at the given slot in memory or creates a new special mload class.
-	Id loadFromMemory(Id _slot, SourceLocation const& _location);
+	Id loadFromMemory(Id _slot, langutil::SourceLocation const& _location);
 	/// Finds or creates a new expression that applies the Keccak-256 hash function to the contents in memory.
-	Id applyKeccak256(Id _start, Id _length, SourceLocation const& _location);
+	Id applyKeccak256(Id _start, Id _length, langutil::SourceLocation const& _location);
 
 	/// @returns a new or already used Id representing the given set of tags.
 	Id tagUnion(std::set<u256> _tags);
diff --git a/libevmasm/SimplificationRules.cpp b/libevmasm/SimplificationRules.cpp
index 120d1787..1dce5f1e 100644
--- a/libevmasm/SimplificationRules.cpp
+++ b/libevmasm/SimplificationRules.cpp
@@ -38,7 +38,7 @@
 using namespace std;
 using namespace dev;
 using namespace dev::eth;
-
+using namespace langutil;
 
 SimplificationRule<Pattern> const* Rules::findFirstMatch(
 	Expression const& _expr,
diff --git a/libevmasm/SimplificationRules.h b/libevmasm/SimplificationRules.h
index fbe5a2b0..fc45a46c 100644
--- a/libevmasm/SimplificationRules.h
+++ b/libevmasm/SimplificationRules.h
@@ -31,6 +31,11 @@
 #include <functional>
 #include <vector>
 
+namespace langutil
+{
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace eth
@@ -97,7 +102,7 @@ public:
 	unsigned matchGroup() const { return m_matchGroup; }
 	bool matches(Expression const& _expr, ExpressionClasses const& _classes) const;
 
-	AssemblyItem toAssemblyItem(SourceLocation const& _location) const;
+	AssemblyItem toAssemblyItem(langutil::SourceLocation const& _location) const;
 	std::vector<Pattern> arguments() const { return m_arguments; }
 
 	/// @returns the id of the matched expression if this pattern is part of a match group.
@@ -135,7 +140,7 @@ struct ExpressionTemplate
 {
 	using Expression = ExpressionClasses::Expression;
 	using Id = ExpressionClasses::Id;
-	explicit ExpressionTemplate(Pattern const& _pattern, SourceLocation const& _location);
+	explicit ExpressionTemplate(Pattern const& _pattern, langutil::SourceLocation const& _location);
 	std::string toString() const;
 	bool hasId = false;
 	/// Id of the matched expression, if available.
diff --git a/liblangutil/CharStream.cpp b/liblangutil/CharStream.cpp
index 04490fa6..aee7cb3e 100644
--- a/liblangutil/CharStream.cpp
+++ b/liblangutil/CharStream.cpp
@@ -52,15 +52,9 @@
 
 #include <liblangutil/CharStream.h>
 #include <liblangutil/Exceptions.h>
-#include <algorithm>
-#include <tuple>
 
 using namespace std;
-
-namespace dev
-{
-namespace solidity
-{
+using namespace langutil;
 
 char CharStream::advanceAndGet(size_t _chars)
 {
@@ -111,5 +105,4 @@ tuple<int, int> CharStream::translatePositionToLineColumn(int _position) const
 	return tuple<int, int>(lineNumber, searchPosition - lineStart);
 }
 
-}
-}
+
diff --git a/liblangutil/CharStream.h b/liblangutil/CharStream.h
index 7c5488a0..72aacacf 100644
--- a/liblangutil/CharStream.h
+++ b/liblangutil/CharStream.h
@@ -56,9 +56,7 @@
 #include <string>
 #include <tuple>
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 
 /**
@@ -97,4 +95,3 @@ private:
 };
 
 }
-}
diff --git a/liblangutil/ErrorReporter.cpp b/liblangutil/ErrorReporter.cpp
index 5edb0eeb..5b6e0072 100644
--- a/liblangutil/ErrorReporter.cpp
+++ b/liblangutil/ErrorReporter.cpp
@@ -21,12 +21,12 @@
  */
 
 #include <liblangutil/ErrorReporter.h>
-#include <libsolidity/ast/AST.h>
+#include <liblangutil/SourceLocation.h>
 #include <memory>
 
 using namespace std;
 using namespace dev;
-using namespace dev::solidity;
+using namespace langutil;
 
 ErrorReporter& ErrorReporter::operator=(ErrorReporter const& _errorReporter)
 {
diff --git a/liblangutil/ErrorReporter.h b/liblangutil/ErrorReporter.h
index 72cf16a4..d90e652e 100644
--- a/liblangutil/ErrorReporter.h
+++ b/liblangutil/ErrorReporter.h
@@ -25,12 +25,8 @@
 #include <liblangutil/Exceptions.h>
 #include <liblangutil/SourceLocation.h>
 
-namespace dev
+namespace langutil
 {
-namespace solidity
-{
-
-class ASTNode;
 
 class ErrorReporter
 {
@@ -120,7 +116,5 @@ private:
 	const unsigned c_maxErrorsAllowed = 256;
 };
 
-
-}
 }
 
diff --git a/liblangutil/Exceptions.cpp b/liblangutil/Exceptions.cpp
index 069619dd..346313d5 100644
--- a/liblangutil/Exceptions.cpp
+++ b/liblangutil/Exceptions.cpp
@@ -24,7 +24,7 @@
 
 using namespace std;
 using namespace dev;
-using namespace dev::solidity;
+using namespace langutil;
 
 Error::Error(Type _type, SourceLocation const& _location, string const& _description):
 	m_type(_type)
diff --git a/liblangutil/Exceptions.h b/liblangutil/Exceptions.h
index 69efd6dd..5ad31ab2 100644
--- a/liblangutil/Exceptions.h
+++ b/liblangutil/Exceptions.h
@@ -24,33 +24,33 @@
 
 #include <string>
 #include <utility>
+#include <vector>
+#include <memory>
 #include <libdevcore/Exceptions.h>
 #include <libdevcore/Assertions.h>
 #include <liblangutil/SourceLocation.h>
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 class Error;
 using ErrorList = std::vector<std::shared_ptr<Error const>>;
 
-struct CompilerError: virtual Exception {};
-struct InternalCompilerError: virtual Exception {};
-struct FatalError: virtual Exception {};
-struct UnimplementedFeatureError: virtual Exception{};
+struct CompilerError: virtual dev::Exception {};
+struct InternalCompilerError: virtual dev::Exception {};
+struct FatalError: virtual dev::Exception {};
+struct UnimplementedFeatureError: virtual dev::Exception {};
 
 /// Assertion that throws an InternalCompilerError containing the given description if it is not met.
 #define solAssert(CONDITION, DESCRIPTION) \
-        assertThrow(CONDITION, ::dev::solidity::InternalCompilerError, DESCRIPTION)
+        assertThrow(CONDITION, ::langutil::InternalCompilerError, DESCRIPTION)
 
 #define solUnimplementedAssert(CONDITION, DESCRIPTION) \
-        assertThrow(CONDITION, ::dev::solidity::UnimplementedFeatureError, DESCRIPTION)
+        assertThrow(CONDITION, ::langutil::UnimplementedFeatureError, DESCRIPTION)
 
 #define solUnimplemented(DESCRIPTION) \
         solUnimplementedAssert(false, DESCRIPTION)
 
-class Error: virtual public Exception
+class Error: virtual public dev::Exception
 {
 public:
 	enum class Type
@@ -98,7 +98,6 @@ private:
 	std::string m_typeName;
 };
 
-
 using errorSourceLocationInfo = std::pair<std::string, SourceLocation>;
 
 class SecondarySourceLocation
@@ -109,6 +108,7 @@ public:
 		infos.push_back(std::make_pair(_errMsg, _sourceLocation));
 		return *this;
 	}
+
 	/// Limits the number of secondary source locations to 32 and appends a notice to the
 	/// error message.
 	void limitSize(std::string& _message)
@@ -124,9 +124,8 @@ public:
 	std::vector<errorSourceLocationInfo> infos;
 };
 
-
 using errinfo_sourceLocation = boost::error_info<struct tag_sourceLocation, SourceLocation>;
 using errinfo_secondarySourceLocation = boost::error_info<struct tag_secondarySourceLocation, SecondarySourceLocation>;
 
-}
+
 }
diff --git a/liblangutil/ParserBase.cpp b/liblangutil/ParserBase.cpp
index 197c2d65..8156f9b9 100644
--- a/liblangutil/ParserBase.cpp
+++ b/liblangutil/ParserBase.cpp
@@ -25,8 +25,7 @@
 #include <liblangutil/ErrorReporter.h>
 
 using namespace std;
-using namespace dev;
-using namespace dev::solidity;
+using namespace langutil;
 
 std::shared_ptr<string const> const& ParserBase::sourceName() const
 {
diff --git a/liblangutil/ParserBase.h b/liblangutil/ParserBase.h
index 0cd94eee..3ecabed5 100644
--- a/liblangutil/ParserBase.h
+++ b/liblangutil/ParserBase.h
@@ -22,12 +22,11 @@
 
 #pragma once
 
-#include <memory>
 #include <liblangutil/Token.h>
+#include <memory>
+#include <string>
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 
 class ErrorReporter;
@@ -90,4 +89,3 @@ protected:
 };
 
 }
-}
diff --git a/liblangutil/Scanner.cpp b/liblangutil/Scanner.cpp
index beb39a4f..3d7527d4 100644
--- a/liblangutil/Scanner.cpp
+++ b/liblangutil/Scanner.cpp
@@ -50,16 +50,14 @@
  * Solidity scanner.
  */
 
-#include <algorithm>
-#include <tuple>
 #include <liblangutil/Exceptions.h>
 #include <liblangutil/Scanner.h>
+#include <algorithm>
+#include <tuple>
 
 using namespace std;
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 
 namespace
@@ -143,10 +141,10 @@ private:
 }; // end of LiteralScope class
 
 
-void Scanner::reset(CharStream const& _source, string const& _sourceName)
+void Scanner::reset(CharStream _source, string _sourceName)
 {
-	m_source = _source;
-	m_sourceName = make_shared<string const>(_sourceName);
+	m_source = std::move(_source);
+	m_sourceName = make_shared<string const>(std::move(_sourceName));
 	reset();
 }
 
@@ -866,5 +864,5 @@ tuple<Token, unsigned, unsigned> Scanner::scanIdentifierOrKeyword()
 	return TokenTraits::fromIdentifierOrKeyword(m_nextToken.literal);
 }
 
-}
+
 }
diff --git a/liblangutil/Scanner.h b/liblangutil/Scanner.h
index 5e5ddfdd..da5e3dfb 100644
--- a/liblangutil/Scanner.h
+++ b/liblangutil/Scanner.h
@@ -52,15 +52,13 @@
 
 #pragma once
 
-#include <libdevcore/Common.h>
-#include <libdevcore/CommonData.h>
+#include <liblangutil/Token.h>
 #include <liblangutil/CharStream.h>
 #include <liblangutil/SourceLocation.h>
-#include <liblangutil/Token.h>
+#include <libdevcore/Common.h>
+#include <libdevcore/CommonData.h>
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 
 class AstRawString;
@@ -71,13 +69,12 @@ class Scanner
 {
 	friend class LiteralScope;
 public:
-
-	explicit Scanner(CharStream const& _source = CharStream(), std::string const& _sourceName = "") { reset(_source, _sourceName); }
+	explicit Scanner(CharStream _source = CharStream(), std::string _sourceName = "") { reset(std::move(_source), std::move(_sourceName)); }
 
 	std::string source() const { return m_source.source(); }
 
 	/// Resets the scanner as if newly constructed with _source and _sourceName as input.
-	void reset(CharStream const& _source, std::string const& _sourceName);
+	void reset(CharStream _source, std::string _sourceName);
 	/// Resets scanner to the start of input.
 	void reset();
 
@@ -216,4 +213,3 @@ private:
 };
 
 }
-}
diff --git a/liblangutil/SourceLocation.h b/liblangutil/SourceLocation.h
index b42c3aa9..eeb81e94 100644
--- a/liblangutil/SourceLocation.h
+++ b/liblangutil/SourceLocation.h
@@ -22,13 +22,13 @@
 
 #pragma once
 
+#include <libdevcore/Common.h> // defines noexcept macro for MSVC
 #include <memory>
 #include <string>
 #include <ostream>
 #include <tuple>
-#include <libdevcore/Common.h> // defines noexcept macro for MSVC
 
-namespace dev
+namespace langutil
 {
 
 /**
diff --git a/liblangutil/Token.cpp b/liblangutil/Token.cpp
index 2e754733..cbfd4a8c 100644
--- a/liblangutil/Token.cpp
+++ b/liblangutil/Token.cpp
@@ -40,15 +40,13 @@
 // You should have received a copy of the GNU General Public License
 // along with solidity.  If not, see <http://www.gnu.org/licenses/>.
 
-#include <map>
 #include <liblangutil/Token.h>
 #include <boost/range/iterator_range.hpp>
+#include <map>
 
 using namespace std;
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 
 void ElementaryTypeNameToken::assertDetails(Token _baseType, unsigned const& _first, unsigned const& _second)
@@ -204,4 +202,3 @@ tuple<Token, unsigned int, unsigned int> fromIdentifierOrKeyword(string const& _
 
 }
 }
-}
diff --git a/liblangutil/Token.h b/liblangutil/Token.h
index 89dd4c01..0b7d9f71 100644
--- a/liblangutil/Token.h
+++ b/liblangutil/Token.h
@@ -45,11 +45,12 @@
 #include <libdevcore/Common.h>
 #include <liblangutil/Exceptions.h>
 #include <liblangutil/UndefMacros.h>
+
 #include <iosfwd>
+#include <string>
+#include <tuple>
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 
 // TOKEN_LIST takes a list of 3 macros M, all of which satisfy the
@@ -375,4 +376,3 @@ private:
 };
 
 }
-}
diff --git a/libsolidity/analysis/ConstantEvaluator.h b/libsolidity/analysis/ConstantEvaluator.h
index ac3a24a1..23ca3628 100644
--- a/libsolidity/analysis/ConstantEvaluator.h
+++ b/libsolidity/analysis/ConstantEvaluator.h
@@ -24,12 +24,16 @@
 
 #include <libsolidity/ast/ASTVisitor.h>
 
+namespace langutil
+{
+class ErrorReporter;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class ErrorReporter;
 class TypeChecker;
 
 /**
@@ -39,7 +43,7 @@ class ConstantEvaluator: private ASTConstVisitor
 {
 public:
 	ConstantEvaluator(
-		ErrorReporter& _errorReporter,
+		langutil::ErrorReporter& _errorReporter,
 		size_t _newDepth = 0,
 		std::shared_ptr<std::map<ASTNode const*, TypePointer>> _types = std::make_shared<std::map<ASTNode const*, TypePointer>>()
 	):
@@ -61,7 +65,7 @@ private:
 	void setType(ASTNode const& _node, TypePointer const& _type);
 	TypePointer type(ASTNode const& _node);
 
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 	/// Current recursion depth.
 	size_t m_depth = 0;
 	std::shared_ptr<std::map<ASTNode const*, TypePointer>> m_types;
diff --git a/libsolidity/analysis/ControlFlowAnalyzer.cpp b/libsolidity/analysis/ControlFlowAnalyzer.cpp
index 8a608552..fe58f0aa 100644
--- a/libsolidity/analysis/ControlFlowAnalyzer.cpp
+++ b/libsolidity/analysis/ControlFlowAnalyzer.cpp
@@ -16,8 +16,10 @@
 */
 
 #include <libsolidity/analysis/ControlFlowAnalyzer.h>
+#include <liblangutil/SourceLocation.h>
 
 using namespace std;
+using namespace langutil;
 using namespace dev::solidity;
 
 bool ControlFlowAnalyzer::analyze(ASTNode const& _astRoot)
diff --git a/libsolidity/analysis/ControlFlowAnalyzer.h b/libsolidity/analysis/ControlFlowAnalyzer.h
index aaaf1bff..411d57ff 100644
--- a/libsolidity/analysis/ControlFlowAnalyzer.h
+++ b/libsolidity/analysis/ControlFlowAnalyzer.h
@@ -29,7 +29,7 @@ namespace solidity
 class ControlFlowAnalyzer: private ASTConstVisitor
 {
 public:
-	explicit ControlFlowAnalyzer(CFG const& _cfg, ErrorReporter& _errorReporter):
+	explicit ControlFlowAnalyzer(CFG const& _cfg, langutil::ErrorReporter& _errorReporter):
 		m_cfg(_cfg), m_errorReporter(_errorReporter) {}
 
 	bool analyze(ASTNode const& _astRoot);
@@ -45,7 +45,7 @@ private:
 	) const;
 
 	CFG const& m_cfg;
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 };
 
 }
diff --git a/libsolidity/analysis/ControlFlowGraph.cpp b/libsolidity/analysis/ControlFlowGraph.cpp
index 9b3da0eb..b8860158 100644
--- a/libsolidity/analysis/ControlFlowGraph.cpp
+++ b/libsolidity/analysis/ControlFlowGraph.cpp
@@ -23,6 +23,7 @@
 #include <algorithm>
 
 using namespace std;
+using namespace langutil;
 using namespace dev::solidity;
 
 bool CFG::constructFlow(ASTNode const& _astRoot)
@@ -133,4 +134,4 @@ void CFG::applyModifierFlowToFunctionFlow(
 
 	_functionFlow->entry = copySrcToCopyDst[_modifierFlow.entry];
 	_functionFlow->exit = copySrcToCopyDst[_modifierFlow.exit];
-}
\ No newline at end of file
+}
diff --git a/libsolidity/analysis/ControlFlowGraph.h b/libsolidity/analysis/ControlFlowGraph.h
index 257ce07f..8fe9fe8e 100644
--- a/libsolidity/analysis/ControlFlowGraph.h
+++ b/libsolidity/analysis/ControlFlowGraph.h
@@ -101,7 +101,7 @@ struct ModifierFlow: FunctionFlow
 class CFG: private ASTConstVisitor
 {
 public:
-	explicit CFG(ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
+	explicit CFG(langutil::ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
 
 	bool constructFlow(ASTNode const& _astRoot);
 
@@ -133,7 +133,7 @@ private:
 		FunctionFlow* _functionFlow
 	);
 
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 
 	/// Node container.
 	/// All nodes allocated during the construction of the control flow graph
diff --git a/libsolidity/analysis/DocStringAnalyser.cpp b/libsolidity/analysis/DocStringAnalyser.cpp
index f91d72f0..69a7a43c 100644
--- a/libsolidity/analysis/DocStringAnalyser.cpp
+++ b/libsolidity/analysis/DocStringAnalyser.cpp
@@ -28,6 +28,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 bool DocStringAnalyser::analyseDocStrings(SourceUnit const& _sourceUnit)
diff --git a/libsolidity/analysis/DocStringAnalyser.h b/libsolidity/analysis/DocStringAnalyser.h
index 82746207..f6b236db 100644
--- a/libsolidity/analysis/DocStringAnalyser.h
+++ b/libsolidity/analysis/DocStringAnalyser.h
@@ -25,13 +25,16 @@
 
 #include <libsolidity/ast/ASTVisitor.h>
 
+namespace langutil
+{
+class ErrorReporter;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class ErrorReporter;
-
 /**
  * Parses and analyses the doc strings.
  * Stores the parsing results in the AST annotations and reports errors.
@@ -39,7 +42,7 @@ class ErrorReporter;
 class DocStringAnalyser: private ASTConstVisitor
 {
 public:
-	DocStringAnalyser(ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
+	DocStringAnalyser(langutil::ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
 	bool analyseDocStrings(SourceUnit const& _sourceUnit);
 
 private:
@@ -75,7 +78,7 @@ private:
 	void appendError(std::string const& _description);
 
 	bool m_errorOccured = false;
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 };
 
 }
diff --git a/libsolidity/analysis/NameAndTypeResolver.cpp b/libsolidity/analysis/NameAndTypeResolver.cpp
index a6c746ed..e40a2c97 100644
--- a/libsolidity/analysis/NameAndTypeResolver.cpp
+++ b/libsolidity/analysis/NameAndTypeResolver.cpp
@@ -30,6 +30,7 @@
 #include <boost/algorithm/string.hpp>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
@@ -59,7 +60,7 @@ bool NameAndTypeResolver::registerDeclarations(SourceUnit& _sourceUnit, ASTNode
 	{
 		DeclarationRegistrationHelper registrar(m_scopes, _sourceUnit, m_errorReporter, _currentScope);
 	}
-	catch (FatalError const&)
+	catch (langutil::FatalError const&)
 	{
 		if (m_errorReporter.errors().empty())
 			throw; // Something is weird here, rather throw again.
@@ -129,7 +130,7 @@ bool NameAndTypeResolver::resolveNamesAndTypes(ASTNode& _node, bool _resolveInsi
 	{
 		return resolveNamesAndTypesInternal(_node, _resolveInsideCode);
 	}
-	catch (FatalError const&)
+	catch (langutil::FatalError const&)
 	{
 		if (m_errorReporter.errors().empty())
 			throw; // Something is weird here, rather throw again.
@@ -144,7 +145,7 @@ bool NameAndTypeResolver::updateDeclaration(Declaration const& _declaration)
 		m_scopes[nullptr]->registerDeclaration(_declaration, nullptr, false, true);
 		solAssert(_declaration.scope() == nullptr, "Updated declaration outside global scope.");
 	}
-	catch (FatalError const&)
+	catch (langutil::FatalError const&)
 	{
 		if (m_errorReporter.errors().empty())
 			throw; // Something is weird here, rather throw again.
diff --git a/libsolidity/analysis/NameAndTypeResolver.h b/libsolidity/analysis/NameAndTypeResolver.h
index a72c21e3..1b034ef4 100644
--- a/libsolidity/analysis/NameAndTypeResolver.h
+++ b/libsolidity/analysis/NameAndTypeResolver.h
@@ -30,13 +30,16 @@
 #include <libsolidity/ast/ASTVisitor.h>
 #include <libsolidity/ast/ASTAnnotations.h>
 
+namespace langutil
+{
+class ErrorReporter;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class ErrorReporter;
-
 /**
  * Resolves name references, typenames and sets the (explicitly given) types for all variable
  * declarations.
@@ -50,7 +53,7 @@ public:
 	NameAndTypeResolver(
 		std::vector<Declaration const*> const& _globals,
 		std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>>& _scopes,
-		ErrorReporter& _errorReporter
+		langutil::ErrorReporter& _errorReporter
 	);
 	/// Registers all declarations found in the AST node, usually a source unit.
 	/// @returns false in case of error.
@@ -125,7 +128,7 @@ private:
 	std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>>& m_scopes;
 
 	DeclarationContainer* m_currentScope = nullptr;
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 };
 
 /**
@@ -142,7 +145,7 @@ public:
 	DeclarationRegistrationHelper(
 		std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>>& _scopes,
 		ASTNode& _astRoot,
-		ErrorReporter& _errorReporter,
+		langutil::ErrorReporter& _errorReporter,
 		ASTNode const* _currentScope = nullptr
 	);
 
@@ -150,10 +153,10 @@ public:
 		DeclarationContainer& _container,
 		Declaration const& _declaration,
 		std::string const* _name,
-		SourceLocation const* _errorLocation,
+		langutil::SourceLocation const* _errorLocation,
 		bool _warnOnShadow,
 		bool _inactive,
-		ErrorReporter& _errorReporter
+		langutil::ErrorReporter& _errorReporter
 	);
 
 private:
@@ -194,7 +197,7 @@ private:
 	std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>>& m_scopes;
 	ASTNode const* m_currentScope = nullptr;
 	VariableScope* m_currentFunction = nullptr;
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 };
 
 }
diff --git a/libsolidity/analysis/PostTypeChecker.cpp b/libsolidity/analysis/PostTypeChecker.cpp
index 3f45df42..27cbcd45 100644
--- a/libsolidity/analysis/PostTypeChecker.cpp
+++ b/libsolidity/analysis/PostTypeChecker.cpp
@@ -29,6 +29,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 
diff --git a/libsolidity/analysis/PostTypeChecker.h b/libsolidity/analysis/PostTypeChecker.h
index 8382948a..e428b81a 100644
--- a/libsolidity/analysis/PostTypeChecker.h
+++ b/libsolidity/analysis/PostTypeChecker.h
@@ -23,13 +23,17 @@
 #include <libsolidity/ast/ASTForward.h>
 #include <libsolidity/ast/ASTVisitor.h>
 
+namespace langutil
+{
+class ErrorReporter;
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class ErrorReporter;
-
 /**
  * This module performs analyses on the AST that are done after type checking and assignments of types:
  *  - whether there are circular references in constant state variables
@@ -39,13 +43,13 @@ class PostTypeChecker: private ASTConstVisitor
 {
 public:
 	/// @param _errorReporter provides the error logging functionality.
-	PostTypeChecker(ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
+	PostTypeChecker(langutil::ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
 
 	bool check(ASTNode const& _astRoot);
 
 private:
 	/// Adds a new error to the list of errors.
-	void typeError(SourceLocation const& _location, std::string const& _description);
+	void typeError(langutil::SourceLocation const& _location, std::string const& _description);
 
 	bool visit(ContractDefinition const& _contract) override;
 	void endVisit(ContractDefinition const& _contract) override;
@@ -57,7 +61,7 @@ private:
 
 	VariableDeclaration const* findCycle(VariableDeclaration const& _startingFrom);
 
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 
 	VariableDeclaration const* m_currentConstVariable = nullptr;
 	std::vector<VariableDeclaration const*> m_constVariables; ///< Required for determinism.
diff --git a/libsolidity/analysis/ReferencesResolver.cpp b/libsolidity/analysis/ReferencesResolver.cpp
index cae92203..7ac3ceff 100644
--- a/libsolidity/analysis/ReferencesResolver.cpp
+++ b/libsolidity/analysis/ReferencesResolver.cpp
@@ -36,9 +36,12 @@
 #include <boost/range/adaptor/transformed.hpp>
 
 using namespace std;
-using namespace dev;
-using namespace dev::solidity;
+using namespace langutil;
 
+namespace dev
+{
+namespace solidity
+{
 
 bool ReferencesResolver::resolve(ASTNode const& _root)
 {
@@ -454,3 +457,6 @@ void ReferencesResolver::fatalDeclarationError(SourceLocation const& _location,
 	m_errorOccurred = true;
 	m_errorReporter.fatalDeclarationError(_location, _description);
 }
+
+}
+}
diff --git a/libsolidity/analysis/ReferencesResolver.h b/libsolidity/analysis/ReferencesResolver.h
index 34dbca96..32c0553f 100644
--- a/libsolidity/analysis/ReferencesResolver.h
+++ b/libsolidity/analysis/ReferencesResolver.h
@@ -28,12 +28,17 @@
 #include <libsolidity/ast/ASTVisitor.h>
 #include <libsolidity/ast/ASTAnnotations.h>
 
+namespace langutil
+{
+class ErrorReporter;
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class ErrorReporter;
 class NameAndTypeResolver;
 
 /**
@@ -44,7 +49,7 @@ class ReferencesResolver: private ASTConstVisitor
 {
 public:
 	ReferencesResolver(
-		ErrorReporter& _errorReporter,
+		langutil::ErrorReporter& _errorReporter,
 		NameAndTypeResolver& _resolver,
 		bool _resolveInsideCode = false
 	):
@@ -77,18 +82,18 @@ private:
 	void endVisit(VariableDeclaration const& _variable) override;
 
 	/// Adds a new error to the list of errors.
-	void typeError(SourceLocation const& _location, std::string const& _description);
+	void typeError(langutil::SourceLocation const& _location, std::string const& _description);
 
 	/// Adds a new error to the list of errors and throws to abort reference resolving.
-	void fatalTypeError(SourceLocation const& _location, std::string const& _description);
+	void fatalTypeError(langutil::SourceLocation const& _location, std::string const& _description);
 
 	/// Adds a new error to the list of errors.
-	void declarationError(SourceLocation const& _location, std::string const& _description);
+	void declarationError(langutil::SourceLocation const& _location, std::string const& _description);
 
 	/// Adds a new error to the list of errors and throws to abort reference resolving.
-	void fatalDeclarationError(SourceLocation const& _location, std::string const& _description);
+	void fatalDeclarationError(langutil::SourceLocation const& _location, std::string const& _description);
 
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 	NameAndTypeResolver& m_resolver;
 	/// Stack of return parameters.
 	std::vector<ParameterList const*> m_returnParameters;
diff --git a/libsolidity/analysis/SemVerHandler.h b/libsolidity/analysis/SemVerHandler.h
index edf4fbd8..80185612 100644
--- a/libsolidity/analysis/SemVerHandler.h
+++ b/libsolidity/analysis/SemVerHandler.h
@@ -22,8 +22,9 @@
 
 #pragma once
 
+#include <libsolidity/parsing/Token.h>
+#include <string>
 #include <vector>
-#include <liblangutil/Token.h>
 
 namespace dev
 {
diff --git a/libsolidity/analysis/StaticAnalyzer.cpp b/libsolidity/analysis/StaticAnalyzer.cpp
index 353c1755..38391841 100644
--- a/libsolidity/analysis/StaticAnalyzer.cpp
+++ b/libsolidity/analysis/StaticAnalyzer.cpp
@@ -28,6 +28,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 bool StaticAnalyzer::analyze(SourceUnit const& _sourceUnit)
diff --git a/libsolidity/analysis/StaticAnalyzer.h b/libsolidity/analysis/StaticAnalyzer.h
index f5f3dbce..ff33fa3a 100644
--- a/libsolidity/analysis/StaticAnalyzer.h
+++ b/libsolidity/analysis/StaticAnalyzer.h
@@ -28,6 +28,11 @@
 #include <libsolidity/ast/ASTForward.h>
 #include <libsolidity/ast/ASTVisitor.h>
 
+namespace langutil
+{
+class ErrorReporter;
+}
+
 namespace dev
 {
 namespace solidity
@@ -44,7 +49,7 @@ class StaticAnalyzer: private ASTConstVisitor
 {
 public:
 	/// @param _errorReporter provides the error logging functionality.
-	explicit StaticAnalyzer(ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
+	explicit StaticAnalyzer(langutil::ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
 
 	/// Performs static analysis on the given source unit and all of its sub-nodes.
 	/// @returns true iff all checks passed. Note even if all checks passed, errors() can still contain warnings
@@ -70,7 +75,7 @@ private:
 	/// @returns the size of this type in storage, including all sub-types.
 	static bigint structureSizeEstimate(Type const& _type, std::set<StructDefinition const*>& _structsSeen);
 
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 
 	/// Flag that indicates whether the current contract definition is a library.
 	bool m_library = false;
diff --git a/libsolidity/analysis/SyntaxChecker.cpp b/libsolidity/analysis/SyntaxChecker.cpp
index 9ac0478e..a73d7e5c 100644
--- a/libsolidity/analysis/SyntaxChecker.cpp
+++ b/libsolidity/analysis/SyntaxChecker.cpp
@@ -29,6 +29,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 
diff --git a/libsolidity/analysis/SyntaxChecker.h b/libsolidity/analysis/SyntaxChecker.h
index 9e3c4652..c2463955 100644
--- a/libsolidity/analysis/SyntaxChecker.h
+++ b/libsolidity/analysis/SyntaxChecker.h
@@ -23,6 +23,11 @@
 #include <libsolidity/ast/ASTForward.h>
 #include <libsolidity/ast/ASTVisitor.h>
 
+namespace langutil
+{
+class ErrorReporter;
+}
+
 namespace dev
 {
 namespace solidity
@@ -39,7 +44,7 @@ class SyntaxChecker: private ASTConstVisitor
 {
 public:
 	/// @param _errorReporter provides the error logging functionality.
-	SyntaxChecker(ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
+	SyntaxChecker(langutil::ErrorReporter& _errorReporter): m_errorReporter(_errorReporter) {}
 
 	bool checkSyntax(ASTNode const& _astRoot);
 
@@ -81,7 +86,7 @@ private:
 	bool visit(StructDefinition const& _struct) override;
 	bool visit(Literal const& _literal) override;
 
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 
 	/// Flag that indicates whether a function modifier actually contains '_'.
 	bool m_placeholderFound = false;
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 7531da65..69de9f12 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -35,6 +35,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace
diff --git a/libsolidity/analysis/TypeChecker.h b/libsolidity/analysis/TypeChecker.h
index 392a923c..c98a4c7f 100644
--- a/libsolidity/analysis/TypeChecker.h
+++ b/libsolidity/analysis/TypeChecker.h
@@ -29,13 +29,16 @@
 #include <libsolidity/ast/ASTForward.h>
 #include <libsolidity/ast/ASTVisitor.h>
 
+namespace langutil
+{
+class ErrorReporter;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class ErrorReporter;
-
 /**
  * The module that performs type analysis on the AST, checks the applicability of operations on
  * those types and stores errors for invalid operations.
@@ -45,7 +48,7 @@ class TypeChecker: private ASTConstVisitor
 {
 public:
 	/// @param _errorReporter provides the error logging functionality.
-	TypeChecker(EVMVersion _evmVersion, ErrorReporter& _errorReporter):
+	TypeChecker(EVMVersion _evmVersion, langutil::ErrorReporter& _errorReporter):
 		m_evmVersion(_evmVersion),
 		m_errorReporter(_errorReporter)
 	{}
@@ -183,7 +186,7 @@ private:
 	/// Flag indicating whether we are currently inside a StructDefinition.
 	bool m_insideStruct = false;
 
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 };
 
 }
diff --git a/libsolidity/analysis/ViewPureChecker.cpp b/libsolidity/analysis/ViewPureChecker.cpp
index b0cacc43..3fb4c026 100644
--- a/libsolidity/analysis/ViewPureChecker.cpp
+++ b/libsolidity/analysis/ViewPureChecker.cpp
@@ -22,10 +22,13 @@
 #include <libsolidity/inlineasm/AsmData.h>
 #include <libsolidity/ast/ExperimentalFeatures.h>
 
+#include <liblangutil/ErrorReporter.h>
+
 #include <functional>
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace
diff --git a/libsolidity/analysis/ViewPureChecker.h b/libsolidity/analysis/ViewPureChecker.h
index 9615d04f..fd2432a7 100644
--- a/libsolidity/analysis/ViewPureChecker.h
+++ b/libsolidity/analysis/ViewPureChecker.h
@@ -21,11 +21,15 @@
 #include <libsolidity/ast/ASTForward.h>
 #include <libsolidity/ast/ASTVisitor.h>
 
-#include <liblangutil/ErrorReporter.h>
-
 #include <map>
 #include <memory>
 
+namespace langutil
+{
+class ErrorReporter;
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace solidity
@@ -34,7 +38,7 @@ namespace solidity
 class ViewPureChecker: private ASTConstVisitor
 {
 public:
-	ViewPureChecker(std::vector<std::shared_ptr<ASTNode>> const& _ast, ErrorReporter& _errorReporter):
+	ViewPureChecker(std::vector<std::shared_ptr<ASTNode>> const& _ast, langutil::ErrorReporter& _errorReporter):
 		m_ast(_ast), m_errorReporter(_errorReporter) {}
 
 	bool check();
@@ -43,7 +47,7 @@ private:
 	struct MutabilityAndLocation
 	{
 		StateMutability mutability;
-		SourceLocation location;
+		langutil::SourceLocation location;
 	};
 
 	bool visit(FunctionDefinition const& _funDef) override;
@@ -62,15 +66,15 @@ private:
 	/// Creates appropriate warnings and errors and sets @a m_currentBestMutability.
 	void reportMutability(
 		StateMutability _mutability,
-		SourceLocation const& _location,
-		boost::optional<SourceLocation> const& _nestedLocation = {}
+		langutil::SourceLocation const& _location,
+		boost::optional<langutil::SourceLocation> const& _nestedLocation = {}
 	);
 
 	std::vector<std::shared_ptr<ASTNode>> const& m_ast;
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 
 	bool m_errors = false;
-	MutabilityAndLocation m_bestMutabilityAndLocation = MutabilityAndLocation{StateMutability::Payable, SourceLocation()};
+	MutabilityAndLocation m_bestMutabilityAndLocation = MutabilityAndLocation{StateMutability::Payable, langutil::SourceLocation()};
 	FunctionDefinition const* m_currentFunction = nullptr;
 	std::map<ModifierDefinition const*, MutabilityAndLocation> m_inferredMutability;
 };
diff --git a/libsolidity/ast/AST.h b/libsolidity/ast/AST.h
index 2c44841e..d23562ad 100644
--- a/libsolidity/ast/AST.h
+++ b/libsolidity/ast/AST.h
@@ -23,8 +23,8 @@
 #pragma once
 
 
+#include <libsolidity/parsing/Token.h>
 #include <libsolidity/ast/ASTForward.h>
-#include <liblangutil/Token.h>
 #include <libsolidity/ast/Types.h>
 #include <libsolidity/ast/ASTAnnotations.h>
 #include <libsolidity/ast/ASTEnums.h>
@@ -58,6 +58,8 @@ class ASTConstVisitor;
 class ASTNode: private boost::noncopyable
 {
 public:
+	using SourceLocation = langutil::SourceLocation;
+
 	explicit ASTNode(SourceLocation const& _location);
 	virtual ~ASTNode();
 
diff --git a/libsolidity/ast/ASTJsonConverter.cpp b/libsolidity/ast/ASTJsonConverter.cpp
index 2d26ce8a..6b9f7227 100644
--- a/libsolidity/ast/ASTJsonConverter.cpp
+++ b/libsolidity/ast/ASTJsonConverter.cpp
@@ -27,6 +27,7 @@
 #include <libsolidity/inlineasm/AsmPrinter.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/libsolidity/ast/ASTJsonConverter.h b/libsolidity/ast/ASTJsonConverter.h
index da0d840a..dec3ac96 100644
--- a/libsolidity/ast/ASTJsonConverter.h
+++ b/libsolidity/ast/ASTJsonConverter.h
@@ -29,6 +29,11 @@
 #include <libsolidity/ast/ASTAnnotations.h>
 #include <json/json.h>
 
+namespace langutil
+{
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace solidity
@@ -120,7 +125,7 @@ private:
 		std::string const& _nodeName,
 		std::vector<std::pair<std::string, Json::Value>>&& _attributes
 	);
-	std::string sourceLocationToString(SourceLocation const& _location) const;
+	std::string sourceLocationToString(langutil::SourceLocation const& _location) const;
 	static std::string namePathToString(std::vector<ASTString> const& _namePath);
 	static Json::Value idOrNull(ASTNode const* _pt)
 	{
diff --git a/libsolidity/ast/ASTPrinter.cpp b/libsolidity/ast/ASTPrinter.cpp
index 255cb9be..cdc6ae7d 100644
--- a/libsolidity/ast/ASTPrinter.cpp
+++ b/libsolidity/ast/ASTPrinter.cpp
@@ -28,6 +28,7 @@
 #include <boost/algorithm/string/join.hpp>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index 4b31d2e8..0eab75aa 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -45,6 +45,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace
diff --git a/libsolidity/ast/Types.h b/libsolidity/ast/Types.h
index 79a656e9..482d6735 100644
--- a/libsolidity/ast/Types.h
+++ b/libsolidity/ast/Types.h
@@ -25,7 +25,7 @@
 #include <liblangutil/Exceptions.h>
 #include <libsolidity/ast/ASTForward.h>
 #include <libsolidity/ast/ASTEnums.h>
-#include <liblangutil/Token.h>
+#include <libsolidity/parsing/Token.h>
 
 #include <libdevcore/Common.h>
 #include <libdevcore/CommonIO.h>
diff --git a/libsolidity/codegen/ArrayUtils.cpp b/libsolidity/codegen/ArrayUtils.cpp
index a4000d60..4878f9f3 100644
--- a/libsolidity/codegen/ArrayUtils.cpp
+++ b/libsolidity/codegen/ArrayUtils.cpp
@@ -30,6 +30,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace solidity;
 
 void ArrayUtils::copyArrayToStorage(ArrayType const& _targetType, ArrayType const& _sourceType) const
diff --git a/libsolidity/codegen/CompilerContext.cpp b/libsolidity/codegen/CompilerContext.cpp
index fa6dfe60..9e4f2882 100644
--- a/libsolidity/codegen/CompilerContext.cpp
+++ b/libsolidity/codegen/CompilerContext.cpp
@@ -26,6 +26,7 @@
 #include <libsolidity/codegen/Compiler.h>
 #include <libsolidity/interface/Version.h>
 #include <liblangutil/ErrorReporter.h>
+#include <liblangutil/Scanner.h>
 #include <libsolidity/interface/SourceReferenceFormatter.h>
 #include <liblangutil/Scanner.h>
 #include <libsolidity/inlineasm/AsmParser.h>
@@ -47,6 +48,7 @@
 
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
@@ -359,7 +361,7 @@ void CompilerContext::appendInlineAssembly(
 
 	ErrorList errors;
 	ErrorReporter errorReporter(errors);
-	auto scanner = make_shared<Scanner>(CharStream(_assembly), "--CODEGEN--");
+	auto scanner = make_shared<langutil::Scanner>(langutil::CharStream(_assembly), "--CODEGEN--");
 	auto parserResult = assembly::Parser(errorReporter, assembly::AsmFlavour::Strict).parse(scanner, false);
 #ifdef SOL_OUTPUT_ASM
 	cout << assembly::AsmPrinter()(*parserResult) << endl;
diff --git a/libsolidity/codegen/CompilerUtils.cpp b/libsolidity/codegen/CompilerUtils.cpp
index a0d11017..93c8cc77 100644
--- a/libsolidity/codegen/CompilerUtils.cpp
+++ b/libsolidity/codegen/CompilerUtils.cpp
@@ -32,6 +32,7 @@
 #include <libdevcore/Whiskers.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/libsolidity/codegen/ContractCompiler.cpp b/libsolidity/codegen/ContractCompiler.cpp
index c8d9d9d3..7a1dcd70 100644
--- a/libsolidity/codegen/ContractCompiler.cpp
+++ b/libsolidity/codegen/ContractCompiler.cpp
@@ -37,6 +37,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index bdf91fbf..57b513d2 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -36,6 +36,7 @@
 #include <libdevcore/Whiskers.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/libsolidity/codegen/LValue.cpp b/libsolidity/codegen/LValue.cpp
index 790ab309..6d71d36f 100644
--- a/libsolidity/codegen/LValue.cpp
+++ b/libsolidity/codegen/LValue.cpp
@@ -28,6 +28,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace solidity;
 
 
diff --git a/libsolidity/codegen/LValue.h b/libsolidity/codegen/LValue.h
index f39eaee1..d854857b 100644
--- a/libsolidity/codegen/LValue.h
+++ b/libsolidity/codegen/LValue.h
@@ -55,17 +55,17 @@ public:
 	/// Copies the value of the current lvalue to the top of the stack and, if @a _remove is true,
 	/// also removes the reference from the stack.
 	/// @a _location source location of the current expression, used for error reporting.
-	virtual void retrieveValue(SourceLocation const& _location, bool _remove = false) const = 0;
+	virtual void retrieveValue(langutil::SourceLocation const& _location, bool _remove = false) const = 0;
 	/// Moves a value from the stack to the lvalue. Removes the value if @a _move is true.
 	/// @a _location is the source location of the expression that caused this operation.
 	/// Stack pre: value [lvalue_ref]
 	/// Stack post: if !_move: value_of(lvalue_ref)
 	virtual void storeValue(Type const& _sourceType,
-		SourceLocation const& _location = SourceLocation(), bool _move = false) const = 0;
+		langutil::SourceLocation const& _location = {}, bool _move = false) const = 0;
 	/// Stores zero in the lvalue. Removes the reference from the stack if @a _removeReference is true.
 	/// @a _location is the source location of the requested operation
 	virtual void setToZero(
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _removeReference = true
 	) const = 0;
 
@@ -83,14 +83,14 @@ public:
 	StackVariable(CompilerContext& _compilerContext, VariableDeclaration const& _declaration);
 
 	unsigned sizeOnStack() const override { return 0; }
-	void retrieveValue(SourceLocation const& _location, bool _remove = false) const override;
+	void retrieveValue(langutil::SourceLocation const& _location, bool _remove = false) const override;
 	virtual void storeValue(
 		Type const& _sourceType,
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _move = false
 	) const override;
 	virtual void setToZero(
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _removeReference = true
 	) const override;
 
@@ -109,14 +109,14 @@ class MemoryItem: public LValue
 public:
 	MemoryItem(CompilerContext& _compilerContext, Type const& _type, bool _padded = true);
 	unsigned sizeOnStack() const override { return 1; }
-	void retrieveValue(SourceLocation const& _location, bool _remove = false) const override;
+	void retrieveValue(langutil::SourceLocation const& _location, bool _remove = false) const override;
 	virtual void storeValue(
 		Type const& _sourceType,
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _move = false
 	) const override;
 	virtual void setToZero(
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _removeReference = true
 	) const override;
 private:
@@ -137,14 +137,14 @@ public:
 	/// Constructs the LValue and assumes that the storage reference is already on the stack.
 	StorageItem(CompilerContext& _compilerContext, Type const& _type);
 	unsigned sizeOnStack() const override { return 2; }
-	void retrieveValue(SourceLocation const& _location, bool _remove = false) const override;
+	void retrieveValue(langutil::SourceLocation const& _location, bool _remove = false) const override;
 	virtual void storeValue(
 		Type const& _sourceType,
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _move = false
 	) const override;
 	virtual void setToZero(
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _removeReference = true
 	) const override;
 };
@@ -159,14 +159,14 @@ public:
 	/// Constructs the LValue and assumes that the storage reference is already on the stack.
 	StorageByteArrayElement(CompilerContext& _compilerContext);
 	unsigned sizeOnStack() const override { return 2; }
-	void retrieveValue(SourceLocation const& _location, bool _remove = false) const override;
+	void retrieveValue(langutil::SourceLocation const& _location, bool _remove = false) const override;
 	virtual void storeValue(
 		Type const& _sourceType,
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _move = false
 	) const override;
 	virtual void setToZero(
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _removeReference = true
 	) const override;
 };
@@ -181,14 +181,14 @@ class StorageArrayLength: public LValue
 public:
 	/// Constructs the LValue, assumes that the reference to the array head is already on the stack.
 	StorageArrayLength(CompilerContext& _compilerContext, ArrayType const& _arrayType);
-	void retrieveValue(SourceLocation const& _location, bool _remove = false) const override;
+	void retrieveValue(langutil::SourceLocation const& _location, bool _remove = false) const override;
 	virtual void storeValue(
 		Type const& _sourceType,
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _move = false
 	) const override;
 	virtual void setToZero(
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _removeReference = true
 	) const override;
 
@@ -206,14 +206,14 @@ public:
 	/// Empty unique_ptrs are possible if e.g. some values should be ignored during assignment.
 	TupleObject(CompilerContext& _compilerContext, std::vector<std::unique_ptr<LValue>>&& _lvalues);
 	unsigned sizeOnStack() const override;
-	void retrieveValue(SourceLocation const& _location, bool _remove = false) const override;
+	void retrieveValue(langutil::SourceLocation const& _location, bool _remove = false) const override;
 	virtual void storeValue(
 		Type const& _sourceType,
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _move = false
 	) const override;
 	virtual void setToZero(
-		SourceLocation const& _location = SourceLocation(),
+		langutil::SourceLocation const& _location = {},
 		bool _removeReference = true
 	) const override;
 
diff --git a/libsolidity/formal/SMTChecker.cpp b/libsolidity/formal/SMTChecker.cpp
index a8595190..7e75df87 100644
--- a/libsolidity/formal/SMTChecker.cpp
+++ b/libsolidity/formal/SMTChecker.cpp
@@ -29,6 +29,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 SMTChecker::SMTChecker(ErrorReporter& _errorReporter, ReadCallback::Callback const& _readFileCallback):
diff --git a/libsolidity/formal/SMTChecker.h b/libsolidity/formal/SMTChecker.h
index ae9f32e9..d7f86cbc 100644
--- a/libsolidity/formal/SMTChecker.h
+++ b/libsolidity/formal/SMTChecker.h
@@ -31,20 +31,25 @@
 #include <string>
 #include <vector>
 
+namespace langutil
+{
+class ErrorReporter;
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
 class VariableUsage;
-class ErrorReporter;
 
 class SMTChecker: private ASTConstVisitor
 {
 public:
-	SMTChecker(ErrorReporter& _errorReporter, ReadCallback::Callback const& _readCallback);
+	SMTChecker(langutil::ErrorReporter& _errorReporter, ReadCallback::Callback const& _readCallback);
 
-	void analyze(SourceUnit const& _sources, std::shared_ptr<Scanner> const& _scanner);
+	void analyze(SourceUnit const& _sources, std::shared_ptr<langutil::Scanner> const& _scanner);
 
 private:
 	// TODO: Check that we do not have concurrent reads and writes to a variable,
@@ -89,8 +94,8 @@ private:
 	/// of rounding for signed division.
 	smt::Expression division(smt::Expression _left, smt::Expression _right, IntegerType const& _type);
 
-	void assignment(VariableDeclaration const& _variable, Expression const& _value, SourceLocation const& _location);
-	void assignment(VariableDeclaration const& _variable, smt::Expression const& _value, SourceLocation const& _location);
+	void assignment(VariableDeclaration const& _variable, Expression const& _value, langutil::SourceLocation const& _location);
+	void assignment(VariableDeclaration const& _variable, smt::Expression const& _value, langutil::SourceLocation const& _location);
 
 	/// Maps a variable to an SSA index.
 	using VariableIndices = std::unordered_map<VariableDeclaration const*, int>;
@@ -104,7 +109,7 @@ private:
 	/// Check that a condition can be satisfied.
 	void checkCondition(
 		smt::Expression _condition,
-		SourceLocation const& _location,
+		langutil::SourceLocation const& _location,
 		std::string const& _description,
 		std::string const& _additionalValueName = "",
 		smt::Expression* _additionalValue = nullptr
@@ -117,7 +122,7 @@ private:
 		std::string const& _description
 	);
 	/// Checks that the value is in the range given by the type.
-	void checkUnderOverflow(smt::Expression _value, IntegerType const& _Type, SourceLocation const& _location);
+	void checkUnderOverflow(smt::Expression _value, IntegerType const& _Type, langutil::SourceLocation const& _location);
 
 
 	std::pair<smt::CheckResult, std::vector<std::string>>
@@ -200,8 +205,8 @@ private:
 	/// Used to retrieve models.
 	std::vector<Expression const*> m_uninterpretedTerms;
 	std::vector<smt::Expression> m_pathConditions;
-	ErrorReporter& m_errorReporter;
-	std::shared_ptr<Scanner> m_scanner;
+	langutil::ErrorReporter& m_errorReporter;
+	std::shared_ptr<langutil::Scanner> m_scanner;
 
 	/// Stores the current path of function calls.
 	std::vector<FunctionDefinition const*> m_functionPath;
diff --git a/libsolidity/inlineasm/AsmAnalysis.cpp b/libsolidity/inlineasm/AsmAnalysis.cpp
index 95c8537d..fb96f73c 100644
--- a/libsolidity/inlineasm/AsmAnalysis.cpp
+++ b/libsolidity/inlineasm/AsmAnalysis.cpp
@@ -35,6 +35,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 using namespace dev::solidity::assembly;
 
diff --git a/libsolidity/inlineasm/AsmAnalysis.h b/libsolidity/inlineasm/AsmAnalysis.h
index 7ae27ebd..194f736e 100644
--- a/libsolidity/inlineasm/AsmAnalysis.h
+++ b/libsolidity/inlineasm/AsmAnalysis.h
@@ -35,11 +35,16 @@
 #include <functional>
 #include <memory>
 
+namespace langutil
+{
+class ErrorReporter;
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace solidity
 {
-class ErrorReporter;
 namespace assembly
 {
 
@@ -55,9 +60,9 @@ class AsmAnalyzer: public boost::static_visitor<bool>
 public:
 	explicit AsmAnalyzer(
 		AsmAnalysisInfo& _analysisInfo,
-		ErrorReporter& _errorReporter,
+		langutil::ErrorReporter& _errorReporter,
 		EVMVersion _evmVersion,
-		boost::optional<Error::Type> _errorTypeForLoose,
+		boost::optional<langutil::Error::Type> _errorTypeForLoose,
 		AsmFlavour _flavour = AsmFlavour::Loose,
 		yul::ExternalIdentifierAccess::Resolver const& _resolver = yul::ExternalIdentifierAccess::Resolver()
 	):
@@ -90,20 +95,20 @@ public:
 private:
 	/// Visits the statement and expects it to deposit one item onto the stack.
 	bool expectExpression(Expression const& _expr);
-	bool expectDeposit(int _deposit, int _oldHeight, SourceLocation const& _location);
+	bool expectDeposit(int _deposit, int _oldHeight, langutil::SourceLocation const& _location);
 
 	/// Verifies that a variable to be assigned to exists and has the same size
 	/// as the value, @a _valueSize, unless that is equal to -1.
 	bool checkAssignment(assembly::Identifier const& _assignment, size_t _valueSize = size_t(-1));
 
 	Scope& scope(assembly::Block const* _block);
-	void expectValidType(std::string const& type, SourceLocation const& _location);
-	void warnOnInstructions(solidity::Instruction _instr, SourceLocation const& _location);
+	void expectValidType(std::string const& type, langutil::SourceLocation const& _location);
+	void warnOnInstructions(solidity::Instruction _instr, langutil::SourceLocation const& _location);
 
 	/// Depending on @a m_flavour and @a m_errorTypeForLoose, throws an internal compiler
 	/// exception (if the flavour is not Loose), reports an error/warning
 	/// (if m_errorTypeForLoose is set) or does nothing.
-	void checkLooseFeature(SourceLocation const& _location, std::string const& _description);
+	void checkLooseFeature(langutil::SourceLocation const& _location, std::string const& _description);
 
 	int m_stackHeight = 0;
 	yul::ExternalIdentifierAccess::Resolver m_resolver;
@@ -112,10 +117,10 @@ private:
 	/// "part of the scope but not yet declared")
 	std::set<Scope::Variable const*> m_activeVariables;
 	AsmAnalysisInfo& m_info;
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 	EVMVersion m_evmVersion;
 	AsmFlavour m_flavour = AsmFlavour::Loose;
-	boost::optional<Error::Type> m_errorTypeForLoose;
+	boost::optional<langutil::Error::Type> m_errorTypeForLoose;
 };
 
 }
diff --git a/libsolidity/inlineasm/AsmCodeGen.cpp b/libsolidity/inlineasm/AsmCodeGen.cpp
index ee69b44f..2800cc7b 100644
--- a/libsolidity/inlineasm/AsmCodeGen.cpp
+++ b/libsolidity/inlineasm/AsmCodeGen.cpp
@@ -46,6 +46,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 using namespace dev::solidity::assembly;
 
diff --git a/libsolidity/inlineasm/AsmData.h b/libsolidity/inlineasm/AsmData.h
index e9bf4841..23a9db75 100644
--- a/libsolidity/inlineasm/AsmData.h
+++ b/libsolidity/inlineasm/AsmData.h
@@ -45,56 +45,56 @@ namespace assembly
 using YulString = dev::yul::YulString;
 using Type = YulString;
 
-struct TypedName { SourceLocation location; YulString name; Type type; };
+struct TypedName { langutil::SourceLocation location; YulString name; Type type; };
 using TypedNameList = std::vector<TypedName>;
 
 /// Direct EVM instruction (except PUSHi and JUMPDEST)
-struct Instruction { SourceLocation location; solidity::Instruction instruction; };
+struct Instruction { langutil::SourceLocation location; solidity::Instruction instruction; };
 /// Literal number or string (up to 32 bytes)
 enum class LiteralKind { Number, Boolean, String };
-struct Literal { SourceLocation location; LiteralKind kind; YulString value; Type type; };
+struct Literal { langutil::SourceLocation location; LiteralKind kind; YulString value; Type type; };
 /// External / internal identifier or label reference
-struct Identifier { SourceLocation location; YulString name; };
+struct Identifier { langutil::SourceLocation location; YulString name; };
 /// Jump label ("name:")
-struct Label { SourceLocation location; YulString name; };
+struct Label { langutil::SourceLocation location; YulString name; };
 /// Assignment from stack (":= x", moves stack top into x, potentially multiple slots)
-struct StackAssignment { SourceLocation location; Identifier variableName; };
+struct StackAssignment { langutil::SourceLocation location; Identifier variableName; };
 /// Assignment ("x := mload(20:u256)", expects push-1-expression on the right hand
 /// side and requires x to occupy exactly one stack slot.
 ///
 /// Multiple assignment ("x, y := f()"), where the left hand side variables each occupy
 /// a single stack slot and expects a single expression on the right hand returning
 /// the same amount of items as the number of variables.
-struct Assignment { SourceLocation location; std::vector<Identifier> variableNames; std::shared_ptr<Expression> value; };
+struct Assignment { langutil::SourceLocation location; std::vector<Identifier> variableNames; std::shared_ptr<Expression> value; };
 /// Functional instruction, e.g. "mul(mload(20:u256), add(2:u256, x))"
-struct FunctionalInstruction { SourceLocation location; solidity::Instruction instruction; std::vector<Expression> arguments; };
-struct FunctionCall { SourceLocation location; Identifier functionName; std::vector<Expression> arguments; };
+struct FunctionalInstruction { langutil::SourceLocation location; solidity::Instruction instruction; std::vector<Expression> arguments; };
+struct FunctionCall { langutil::SourceLocation location; Identifier functionName; std::vector<Expression> arguments; };
 /// Statement that contains only a single expression
-struct ExpressionStatement { SourceLocation location; Expression expression; };
+struct ExpressionStatement { langutil::SourceLocation location; Expression expression; };
 /// Block-scope variable declaration ("let x:u256 := mload(20:u256)"), non-hoisted
-struct VariableDeclaration { SourceLocation location; TypedNameList variables; std::shared_ptr<Expression> value; };
+struct VariableDeclaration { langutil::SourceLocation location; TypedNameList variables; std::shared_ptr<Expression> value; };
 /// Block that creates a scope (frees declared stack variables)
-struct Block { SourceLocation location; std::vector<Statement> statements; };
+struct Block { langutil::SourceLocation location; std::vector<Statement> statements; };
 /// Function definition ("function f(a, b) -> (d, e) { ... }")
-struct FunctionDefinition { SourceLocation location; YulString name; TypedNameList parameters; TypedNameList returnVariables; Block body; };
+struct FunctionDefinition { langutil::SourceLocation location; YulString name; TypedNameList parameters; TypedNameList returnVariables; Block body; };
 /// Conditional execution without "else" part.
-struct If { SourceLocation location; std::shared_ptr<Expression> condition; Block body; };
+struct If { langutil::SourceLocation location; std::shared_ptr<Expression> condition; Block body; };
 /// Switch case or default case
-struct Case { SourceLocation location; std::shared_ptr<Literal> value; Block body; };
+struct Case { langutil::SourceLocation location; std::shared_ptr<Literal> value; Block body; };
 /// Switch statement
-struct Switch { SourceLocation location; std::shared_ptr<Expression> expression; std::vector<Case> cases; };
-struct ForLoop { SourceLocation location; Block pre; std::shared_ptr<Expression> condition; Block post; Block body; };
+struct Switch { langutil::SourceLocation location; std::shared_ptr<Expression> expression; std::vector<Case> cases; };
+struct ForLoop { langutil::SourceLocation location; Block pre; std::shared_ptr<Expression> condition; Block post; Block body; };
 
-struct LocationExtractor: boost::static_visitor<SourceLocation>
+struct LocationExtractor: boost::static_visitor<langutil::SourceLocation>
 {
-	template <class T> SourceLocation operator()(T const& _node) const
+	template <class T> langutil::SourceLocation operator()(T const& _node) const
 	{
 		return _node.location;
 	}
 };
 
 /// Extracts the source location from an inline assembly node.
-template <class T> inline SourceLocation locationOf(T const& _node)
+template <class T> inline langutil::SourceLocation locationOf(T const& _node)
 {
 	return boost::apply_visitor(LocationExtractor(), _node);
 }
diff --git a/libsolidity/inlineasm/AsmParser.cpp b/libsolidity/inlineasm/AsmParser.cpp
index 3103e2b3..b11f70e0 100644
--- a/libsolidity/inlineasm/AsmParser.cpp
+++ b/libsolidity/inlineasm/AsmParser.cpp
@@ -31,6 +31,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 using namespace dev::solidity::assembly;
 
diff --git a/libsolidity/inlineasm/AsmParser.h b/libsolidity/inlineasm/AsmParser.h
index b3d74df1..9e13799a 100644
--- a/libsolidity/inlineasm/AsmParser.h
+++ b/libsolidity/inlineasm/AsmParser.h
@@ -25,6 +25,8 @@
 #include <memory>
 #include <vector>
 #include <libsolidity/inlineasm/AsmData.h>
+#include <liblangutil/SourceLocation.h>
+#include <liblangutil/Scanner.h>
 #include <liblangutil/ParserBase.h>
 
 namespace dev
@@ -34,22 +36,22 @@ namespace solidity
 namespace assembly
 {
 
-class Parser: public ParserBase
+class Parser: public langutil::ParserBase
 {
 public:
-	explicit Parser(ErrorReporter& _errorReporter, AsmFlavour _flavour = AsmFlavour::Loose):
+	explicit Parser(langutil::ErrorReporter& _errorReporter, AsmFlavour _flavour = AsmFlavour::Loose):
 		ParserBase(_errorReporter), m_flavour(_flavour) {}
 
 	/// Parses an inline assembly block starting with `{` and ending with `}`.
 	/// @param _reuseScanner if true, do check for end of input after the `}`.
 	/// @returns an empty shared pointer on error.
-	std::shared_ptr<Block> parse(std::shared_ptr<Scanner> const& _scanner, bool _reuseScanner);
+	std::shared_ptr<Block> parse(std::shared_ptr<langutil::Scanner> const& _scanner, bool _reuseScanner);
 
 protected:
 	using ElementaryOperation = boost::variant<assembly::Instruction, assembly::Literal, assembly::Identifier>;
 
 	/// Creates an inline assembly node with the given source location.
-	template <class T> T createWithLocation(SourceLocation const& _loc = SourceLocation()) const
+	template <class T> T createWithLocation(langutil::SourceLocation const& _loc = {}) const
 	{
 		T r;
 		r.location = _loc;
@@ -62,7 +64,7 @@ protected:
 			r.location.sourceName = sourceName();
 		return r;
 	}
-	SourceLocation location() const { return SourceLocation(position(), endPosition(), sourceName()); }
+	langutil::SourceLocation location() const { return {position(), endPosition(), sourceName()}; }
 
 	Block parseBlock();
 	Statement parseStatement();
diff --git a/libsolidity/inlineasm/AsmScopeFiller.cpp b/libsolidity/inlineasm/AsmScopeFiller.cpp
index c7625fe0..09934bd8 100644
--- a/libsolidity/inlineasm/AsmScopeFiller.cpp
+++ b/libsolidity/inlineasm/AsmScopeFiller.cpp
@@ -36,6 +36,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 using namespace dev::solidity::assembly;
 
diff --git a/libsolidity/inlineasm/AsmScopeFiller.h b/libsolidity/inlineasm/AsmScopeFiller.h
index bb023f61..7454fd6c 100644
--- a/libsolidity/inlineasm/AsmScopeFiller.h
+++ b/libsolidity/inlineasm/AsmScopeFiller.h
@@ -27,12 +27,16 @@
 #include <functional>
 #include <memory>
 
-namespace dev
+namespace langutil
 {
+class ErrorReporter;
 struct SourceLocation;
+}
+
+namespace dev
+{
 namespace solidity
 {
-class ErrorReporter;
 namespace assembly
 {
 
@@ -47,7 +51,7 @@ struct AsmAnalysisInfo;
 class ScopeFiller: public boost::static_visitor<bool>
 {
 public:
-	ScopeFiller(AsmAnalysisInfo& _info, ErrorReporter& _errorReporter);
+	ScopeFiller(AsmAnalysisInfo& _info, langutil::ErrorReporter& _errorReporter);
 
 	bool operator()(assembly::Instruction const&) { return true; }
 	bool operator()(assembly::Literal const&) { return true; }
@@ -68,7 +72,7 @@ public:
 private:
 	bool registerVariable(
 		TypedName const& _name,
-		SourceLocation const& _location,
+		langutil::SourceLocation const& _location,
 		Scope& _scope
 	);
 
@@ -76,7 +80,7 @@ private:
 
 	Scope* m_currentScope = nullptr;
 	AsmAnalysisInfo& m_info;
-	ErrorReporter& m_errorReporter;
+	langutil::ErrorReporter& m_errorReporter;
 };
 
 }
diff --git a/libsolidity/interface/AssemblyStack.cpp b/libsolidity/interface/AssemblyStack.cpp
index 26879e8b..5b6b1113 100644
--- a/libsolidity/interface/AssemblyStack.cpp
+++ b/libsolidity/interface/AssemblyStack.cpp
@@ -36,6 +36,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace
diff --git a/libsolidity/interface/AssemblyStack.h b/libsolidity/interface/AssemblyStack.h
index aad65ffc..d6ee33cf 100644
--- a/libsolidity/interface/AssemblyStack.h
+++ b/libsolidity/interface/AssemblyStack.h
@@ -29,11 +29,15 @@
 #include <string>
 #include <memory>
 
+namespace langutil
+{
+class Scanner;
+}
+
 namespace dev
 {
 namespace solidity
 {
-class Scanner;
 namespace assembly
 {
 struct AsmAnalysisInfo;
@@ -61,7 +65,7 @@ public:
 	{}
 
 	/// @returns the scanner used during parsing
-	Scanner const& scanner() const;
+	langutil::Scanner const& scanner() const;
 
 	/// Runs parsing and analysis steps, returns false if input cannot be assembled.
 	/// Multiple calls overwrite the previous state.
@@ -69,13 +73,13 @@ public:
 
 	/// Runs analysis step on the supplied block, returns false if input cannot be assembled.
 	/// Multiple calls overwrite the previous state.
-	bool analyze(assembly::Block const& _block, Scanner const* _scanner = nullptr);
+	bool analyze(assembly::Block const& _block, langutil::Scanner const* _scanner = nullptr);
 
 	/// Run the assembly step (should only be called after parseAndAnalyze).
 	MachineAssemblyObject assemble(Machine _machine) const;
 
 	/// @returns the errors generated during parsing, analysis (and potentially assembly).
-	ErrorList const& errors() const { return m_errors; }
+	langutil::ErrorList const& errors() const { return m_errors; }
 
 	/// Pretty-print the input after having parsed it.
 	std::string print() const;
@@ -86,13 +90,13 @@ private:
 	Language m_language = Language::Assembly;
 	EVMVersion m_evmVersion;
 
-	std::shared_ptr<Scanner> m_scanner;
+	std::shared_ptr<langutil::Scanner> m_scanner;
 
 	bool m_analysisSuccessful = false;
 	std::shared_ptr<assembly::Block> m_parserResult;
 	std::shared_ptr<assembly::AsmAnalysisInfo> m_analysisInfo;
-	ErrorList m_errors;
-	ErrorReporter m_errorReporter;
+	langutil::ErrorList m_errors;
+	langutil::ErrorReporter m_errorReporter;
 };
 
 }
diff --git a/libsolidity/interface/CompilerStack.cpp b/libsolidity/interface/CompilerStack.cpp
index 08a248dd..a5674705 100644
--- a/libsolidity/interface/CompilerStack.cpp
+++ b/libsolidity/interface/CompilerStack.cpp
@@ -58,6 +58,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 boost::optional<CompilerStack::Remapping> CompilerStack::parseRemapping(string const& _remapping)
diff --git a/libsolidity/interface/CompilerStack.h b/libsolidity/interface/CompilerStack.h
index a7e312ad..8c50266e 100644
--- a/libsolidity/interface/CompilerStack.h
+++ b/libsolidity/interface/CompilerStack.h
@@ -23,11 +23,12 @@
 
 #pragma once
 
-#include <liblangutil/ErrorReporter.h>
 #include <libsolidity/interface/ReadFile.h>
-#include <liblangutil/EVMVersion.h>
 
+#include <liblangutil/ErrorReporter.h>
+#include <liblangutil/EVMVersion.h>
 #include <liblangutil/SourceLocation.h>
+
 #include <libevmasm/LinkerObject.h>
 
 #include <libdevcore/Common.h>
@@ -43,6 +44,11 @@
 #include <vector>
 #include <functional>
 
+namespace langutil
+{
+class Scanner;
+}
+
 namespace dev
 {
 
@@ -57,7 +63,6 @@ namespace solidity
 {
 
 // forward declarations
-class Scanner;
 class ASTNode;
 class ContractDefinition;
 class FunctionDefinition;
@@ -65,7 +70,6 @@ class SourceUnit;
 class Compiler;
 class GlobalContext;
 class Natspec;
-class Error;
 class DeclarationContainer;
 
 /**
@@ -100,7 +104,7 @@ public:
 		m_errorReporter(m_errorList) {}
 
 	/// @returns the list of errors that occurred during parsing and type checking.
-	ErrorList const& errors() const { return m_errorReporter.errors(); }
+	langutil::ErrorList const& errors() const { return m_errorReporter.errors(); }
 
 	/// @returns the current state.
 	State state() const { return m_stackState; }
@@ -174,7 +178,7 @@ public:
 	std::map<std::string, unsigned> sourceIndices() const;
 
 	/// @returns the previously used scanner, useful for counting lines during error reporting.
-	Scanner const& scanner(std::string const& _sourceName) const;
+	langutil::Scanner const& scanner(std::string const& _sourceName) const;
 
 	/// @returns the parsed source unit with the supplied name.
 	SourceUnit const& ast(std::string const& _sourceName) const;
@@ -182,7 +186,7 @@ public:
 	/// Helper function for logs printing. Do only use in error cases, it's quite expensive.
 	/// line and columns are numbered starting from 1 with following order:
 	/// start line, start column, end line, end column
-	std::tuple<int, int, int, int> positionFromSourceLocation(SourceLocation const& _sourceLocation) const;
+	std::tuple<int, int, int, int> positionFromSourceLocation(langutil::SourceLocation const& _sourceLocation) const;
 
 	/// @returns a list of the contract names in the sources.
 	std::vector<std::string> contractNames() const;
@@ -248,7 +252,7 @@ private:
 	/// The state per source unit. Filled gradually during parsing.
 	struct Source
 	{
-		std::shared_ptr<Scanner> scanner;
+		std::shared_ptr<langutil::Scanner> scanner;
 		std::shared_ptr<SourceUnit> ast;
 		bool isLibrary = false;
 		void reset() { scanner.reset(); ast.reset(); }
@@ -345,8 +349,8 @@ private:
 	/// This is updated during compilation.
 	std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>> m_scopes;
 	std::map<std::string const, Contract> m_contracts;
-	ErrorList m_errorList;
-	ErrorReporter m_errorReporter;
+	langutil::ErrorList m_errorList;
+	langutil::ErrorReporter m_errorReporter;
 	bool m_metadataLiteralSources = false;
 	State m_stackState = Empty;
 };
diff --git a/libsolidity/interface/GasEstimator.cpp b/libsolidity/interface/GasEstimator.cpp
index 1f20366e..de6b2ce5 100644
--- a/libsolidity/interface/GasEstimator.cpp
+++ b/libsolidity/interface/GasEstimator.cpp
@@ -35,6 +35,7 @@
 using namespace std;
 using namespace dev;
 using namespace dev::eth;
+using namespace langutil;
 using namespace dev::solidity;
 
 GasEstimator::ASTGasConsumptionSelfAccumulated GasEstimator::structuralEstimation(
diff --git a/libsolidity/interface/SourceReferenceFormatter.cpp b/libsolidity/interface/SourceReferenceFormatter.cpp
index 9e2c988e..d727afbe 100644
--- a/libsolidity/interface/SourceReferenceFormatter.cpp
+++ b/libsolidity/interface/SourceReferenceFormatter.cpp
@@ -25,6 +25,7 @@
 #include <liblangutil/Exceptions.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/libsolidity/interface/SourceReferenceFormatter.h b/libsolidity/interface/SourceReferenceFormatter.h
index 281a4bdc..7dea5254 100644
--- a/libsolidity/interface/SourceReferenceFormatter.h
+++ b/libsolidity/interface/SourceReferenceFormatter.h
@@ -25,7 +25,12 @@
 #include <ostream>
 #include <sstream>
 #include <functional>
-#include <liblangutil/SourceLocation.h>
+
+namespace langutil
+{
+struct SourceLocation;
+class Scanner;
+}
 
 namespace dev
 {
@@ -35,13 +40,12 @@ struct Exception; // forward
 namespace solidity
 {
 
-class Scanner; // forward
 class CompilerStack; // forward
 
 class SourceReferenceFormatter
 {
 public:
-	using ScannerFromSourceNameFun = std::function<Scanner const&(std::string const&)>;
+	using ScannerFromSourceNameFun = std::function<langutil::Scanner const&(std::string const&)>;
 
 	explicit SourceReferenceFormatter(
 		std::ostream& _stream,
@@ -52,7 +56,7 @@ public:
 	{}
 
 	/// Prints source location if it is given.
-	void printSourceLocation(SourceLocation const* _location);
+	void printSourceLocation(langutil::SourceLocation const* _location);
 	void printExceptionInformation(Exception const& _exception, std::string const& _name);
 
 	static std::string formatExceptionInformation(
@@ -69,7 +73,7 @@ public:
 	}
 private:
 	/// Prints source name if location is given.
-	void printSourceName(SourceLocation const* _location);
+	void printSourceName(langutil::SourceLocation const* _location);
 
 	std::ostream& m_stream;
 	ScannerFromSourceNameFun m_scannerFromSourceName;
diff --git a/libsolidity/interface/StandardCompiler.cpp b/libsolidity/interface/StandardCompiler.cpp
index c8b03a94..291a1071 100644
--- a/libsolidity/interface/StandardCompiler.cpp
+++ b/libsolidity/interface/StandardCompiler.cpp
@@ -31,6 +31,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace {
@@ -411,7 +412,7 @@ Json::Value StandardCompiler::compileInternal(Json::Value const& _input)
 	Json::Value outputSelection = settings.get("outputSelection", Json::Value());
 	m_compilerStack.setRequestedContractNames(requestedContractNames(outputSelection));
 
-	auto scannerFromSourceName = [&](string const& _sourceName) -> solidity::Scanner const& { return m_compilerStack.scanner(_sourceName); };
+	auto scannerFromSourceName = [&](string const& _sourceName) -> Scanner const& { return m_compilerStack.scanner(_sourceName); };
 
 	try
 	{
diff --git a/libsolidity/parsing/DocStringParser.cpp b/libsolidity/parsing/DocStringParser.cpp
index 17a7b691..d8927fea 100644
--- a/libsolidity/parsing/DocStringParser.cpp
+++ b/libsolidity/parsing/DocStringParser.cpp
@@ -8,6 +8,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 
diff --git a/libsolidity/parsing/DocStringParser.h b/libsolidity/parsing/DocStringParser.h
index 5f2819cc..c83b416d 100644
--- a/libsolidity/parsing/DocStringParser.h
+++ b/libsolidity/parsing/DocStringParser.h
@@ -25,19 +25,22 @@
 #include <string>
 #include <libsolidity/ast/ASTAnnotations.h>
 
+namespace langutil
+{
+class ErrorReporter;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class ErrorReporter;
-
 class DocStringParser
 {
 public:
 	/// Parse the given @a _docString and stores the parsed components internally.
 	/// @returns false on error and appends the error to @a _errors.
-	bool parse(std::string const& _docString, ErrorReporter& _errorReporter);
+	bool parse(std::string const& _docString, langutil::ErrorReporter& _errorReporter);
 
 	std::multimap<std::string, DocTag> const& tags() const { return m_docTags; }
 
@@ -63,7 +66,7 @@ private:
 	/// Mapping tag name -> content.
 	std::multimap<std::string, DocTag> m_docTags;
 	DocTag* m_lastTag = nullptr;
-	ErrorReporter* m_errorReporter = nullptr;
+	langutil::ErrorReporter* m_errorReporter = nullptr;
 	bool m_errorsOccurred = false;
 };
 
diff --git a/libsolidity/parsing/Parser.cpp b/libsolidity/parsing/Parser.cpp
index f070620d..de5293b4 100644
--- a/libsolidity/parsing/Parser.cpp
+++ b/libsolidity/parsing/Parser.cpp
@@ -29,6 +29,7 @@
 #include <liblangutil/ErrorReporter.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/libsolidity/parsing/Parser.h b/libsolidity/parsing/Parser.h
index f20f01c5..15852096 100644
--- a/libsolidity/parsing/Parser.h
+++ b/libsolidity/parsing/Parser.h
@@ -25,19 +25,22 @@
 #include <libsolidity/ast/AST.h>
 #include <liblangutil/ParserBase.h>
 
+namespace langutil
+{
+class Scanner;
+}
+
 namespace dev
 {
 namespace solidity
 {
 
-class Scanner;
-
-class Parser: public ParserBase
+class Parser: public langutil::ParserBase
 {
 public:
-	explicit Parser(ErrorReporter& _errorReporter): ParserBase(_errorReporter) {}
+	explicit Parser(langutil::ErrorReporter& _errorReporter): ParserBase(_errorReporter) {}
 
-	ASTPointer<SourceUnit> parse(std::shared_ptr<Scanner> const& _scanner);
+	ASTPointer<SourceUnit> parse(std::shared_ptr<langutil::Scanner> const& _scanner);
 
 private:
 	class ASTNodeFactory;
@@ -146,7 +149,7 @@ private:
 	struct IndexAccessedPath
 	{
 		std::vector<ASTPointer<PrimaryExpression>> path;
-		std::vector<std::pair<ASTPointer<Expression>, SourceLocation>> indices;
+		std::vector<std::pair<ASTPointer<Expression>, langutil::SourceLocation>> indices;
 		bool empty() const;
 	};
 
diff --git a/libsolidity/parsing/Token.h b/libsolidity/parsing/Token.h
new file mode 100644
index 00000000..d61aefb6
--- /dev/null
+++ b/libsolidity/parsing/Token.h
@@ -0,0 +1,36 @@
+/*
+    This file is part of solidity.
+
+    solidity is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    solidity is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Solidity and Yul both share the same Token (and Scanner) API.
+ *
+ * This may (or may not) change in the future. But for the time being, we've put both
+ * at a shared place, and *just* import them.
+*/
+#pragma once
+
+#include <liblangutil/Token.h>
+
+namespace dev
+{
+namespace solidity
+{
+namespace TokenTraits = ::langutil::TokenTraits;
+
+using ::langutil::Token;
+using ::langutil::ElementaryTypeNameToken;
+}
+}
diff --git a/libyul/backends/evm/AbstractAssembly.h b/libyul/backends/evm/AbstractAssembly.h
index d75058f7..5a1140cb 100644
--- a/libyul/backends/evm/AbstractAssembly.h
+++ b/libyul/backends/evm/AbstractAssembly.h
@@ -26,9 +26,13 @@
 
 #include <functional>
 
-namespace dev
+namespace langutil
 {
 struct SourceLocation;
+}
+
+namespace dev
+{
 namespace solidity
 {
 enum class Instruction: uint8_t;
@@ -52,7 +56,7 @@ public:
 	virtual ~AbstractAssembly() {}
 
 	/// Set a new source location valid starting from the next instruction.
-	virtual void setSourceLocation(SourceLocation const& _location) = 0;
+	virtual void setSourceLocation(langutil::SourceLocation const& _location) = 0;
 	/// Retrieve the current height of the stack. This does not have to be zero
 	/// at the beginning.
 	virtual int stackHeight() const = 0;
diff --git a/libyul/backends/evm/EVMAssembly.cpp b/libyul/backends/evm/EVMAssembly.cpp
index e4ba37f0..791b6226 100644
--- a/libyul/backends/evm/EVMAssembly.cpp
+++ b/libyul/backends/evm/EVMAssembly.cpp
@@ -26,6 +26,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::yul;
 
 namespace
diff --git a/libyul/backends/evm/EVMAssembly.h b/libyul/backends/evm/EVMAssembly.h
index 8f92b6e7..c9190634 100644
--- a/libyul/backends/evm/EVMAssembly.h
+++ b/libyul/backends/evm/EVMAssembly.h
@@ -26,6 +26,11 @@
 
 #include <map>
 
+namespace langutil
+{
+struct SourceLocation;
+}
+
 namespace dev
 {
 namespace yul
@@ -38,7 +43,7 @@ public:
 	virtual ~EVMAssembly() {}
 
 	/// Set a new source location valid starting from the next instruction.
-	void setSourceLocation(SourceLocation const& _location) override;
+	void setSourceLocation(langutil::SourceLocation const& _location) override;
 	/// Retrieve the current height of the stack. This does not have to be zero
 	/// at the beginning.
 	int stackHeight() const override { return m_stackHeight; }
diff --git a/libyul/optimiser/ExpressionSplitter.cpp b/libyul/optimiser/ExpressionSplitter.cpp
index a4b7a909..42730864 100644
--- a/libyul/optimiser/ExpressionSplitter.cpp
+++ b/libyul/optimiser/ExpressionSplitter.cpp
@@ -31,6 +31,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::yul;
 using namespace dev::solidity;
 
diff --git a/libyul/optimiser/SSATransform.cpp b/libyul/optimiser/SSATransform.cpp
index f209ee7b..6fb4b08d 100644
--- a/libyul/optimiser/SSATransform.cpp
+++ b/libyul/optimiser/SSATransform.cpp
@@ -31,6 +31,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::yul;
 using namespace dev::solidity;
 
diff --git a/libyul/optimiser/SimplificationRules.cpp b/libyul/optimiser/SimplificationRules.cpp
index 5721042f..a15ed391 100644
--- a/libyul/optimiser/SimplificationRules.cpp
+++ b/libyul/optimiser/SimplificationRules.cpp
@@ -31,6 +31,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::yul;
 
 
diff --git a/libyul/optimiser/SimplificationRules.h b/libyul/optimiser/SimplificationRules.h
index b608ca91..bd6aa4de 100644
--- a/libyul/optimiser/SimplificationRules.h
+++ b/libyul/optimiser/SimplificationRules.h
@@ -107,7 +107,7 @@ public:
 
 	/// Turns this pattern into an actual expression. Should only be called
 	/// for patterns resulting from an action, i.e. with match groups assigned.
-	Expression toExpression(SourceLocation const& _location) const;
+	Expression toExpression(langutil::SourceLocation const& _location) const;
 
 private:
 	Expression const& matchGroupValue() const;
diff --git a/solc/CommandLineInterface.cpp b/solc/CommandLineInterface.cpp
index 357d0ab3..b9f0bf79 100644
--- a/solc/CommandLineInterface.cpp
+++ b/solc/CommandLineInterface.cpp
@@ -62,6 +62,7 @@
 #include <fstream>
 
 using namespace std;
+using namespace langutil;
 namespace po = boost::program_options;
 
 namespace dev
@@ -827,7 +828,7 @@ bool CommandLineInterface::processInput()
 
 	m_compiler.reset(new CompilerStack(fileReader));
 
-	auto scannerFromSourceName = [&](string const& _sourceName) -> solidity::Scanner const& { return m_compiler->scanner(_sourceName); };
+	auto scannerFromSourceName = [&](string const& _sourceName) -> Scanner const& { return m_compiler->scanner(_sourceName); };
 	SourceReferenceFormatter formatter(cerr, scannerFromSourceName);
 
 	try
diff --git a/test/libevmasm/Assembler.cpp b/test/libevmasm/Assembler.cpp
index 1c041596..5ad01594 100644
--- a/test/libevmasm/Assembler.cpp
+++ b/test/libevmasm/Assembler.cpp
@@ -30,6 +30,7 @@
 #include <memory>
 
 using namespace std;
+using namespace langutil;
 using namespace dev::eth;
 
 namespace dev
diff --git a/test/libevmasm/Optimiser.cpp b/test/libevmasm/Optimiser.cpp
index c01e8758..c061b783 100644
--- a/test/libevmasm/Optimiser.cpp
+++ b/test/libevmasm/Optimiser.cpp
@@ -36,6 +36,7 @@
 #include <memory>
 
 using namespace std;
+using namespace langutil;
 using namespace dev::eth;
 
 namespace dev
diff --git a/test/liblangutil/SourceLocation.cpp b/test/liblangutil/SourceLocation.cpp
index 29cfb6a0..ac7a2173 100644
--- a/test/liblangutil/SourceLocation.cpp
+++ b/test/liblangutil/SourceLocation.cpp
@@ -24,9 +24,7 @@
 
 #include <test/Options.h>
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 namespace test
 {
@@ -46,5 +44,4 @@ BOOST_AUTO_TEST_CASE(test_fail)
 BOOST_AUTO_TEST_SUITE_END()
 
 }
-}
 } // end namespaces
diff --git a/test/libsolidity/AnalysisFramework.cpp b/test/libsolidity/AnalysisFramework.cpp
index dafd1748..12d63cb7 100644
--- a/test/libsolidity/AnalysisFramework.cpp
+++ b/test/libsolidity/AnalysisFramework.cpp
@@ -35,6 +35,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 using namespace dev::solidity::test;
 
@@ -127,7 +128,7 @@ string AnalysisFramework::formatError(Error const& _error) const
 	return SourceReferenceFormatter::formatExceptionInformation(
 			_error,
 			(_error.type() == Error::Type::Warning) ? "Warning" : "Error",
-			[&](std::string const& _sourceName) -> solidity::Scanner const& { return m_compiler.scanner(_sourceName); }
+			[&](std::string const& _sourceName) -> Scanner const& { return m_compiler.scanner(_sourceName); }
 		);
 }
 
diff --git a/test/libsolidity/AnalysisFramework.h b/test/libsolidity/AnalysisFramework.h
index a904617d..391a21da 100644
--- a/test/libsolidity/AnalysisFramework.h
+++ b/test/libsolidity/AnalysisFramework.h
@@ -45,7 +45,7 @@ class AnalysisFramework
 {
 
 protected:
-	virtual std::pair<SourceUnit const*, ErrorList>
+	virtual std::pair<SourceUnit const*, langutil::ErrorList>
 	parseAnalyseAndReturnError(
 		std::string const& _source,
 		bool _reportWarnings = false,
@@ -56,10 +56,10 @@ protected:
 
 	SourceUnit const* parseAndAnalyse(std::string const& _source);
 	bool success(std::string const& _source);
-	ErrorList expectError(std::string const& _source, bool _warning = false, bool _allowMultiple = false);
+	langutil::ErrorList expectError(std::string const& _source, bool _warning = false, bool _allowMultiple = false);
 
 	std::string formatErrors() const;
-	std::string formatError(Error const& _error) const;
+	std::string formatError(langutil::Error const& _error) const;
 
 	static ContractDefinition const* retrieveContractByName(SourceUnit const& _source, std::string const& _name);
 	static FunctionTypePointer retrieveFunctionBySignature(
@@ -68,7 +68,7 @@ protected:
 	);
 
 	// filter out the warnings in m_warningsToFilter or all warnings if _includeWarnings is false
-	ErrorList filterErrors(ErrorList const& _errorList, bool _includeWarnings) const;
+	langutil::ErrorList filterErrors(langutil::ErrorList const& _errorList, bool _includeWarnings) const;
 
 	std::vector<std::string> m_warningsToFilter = {"This is a pre-release compiler version"};
 	dev::solidity::CompilerStack m_compiler;
diff --git a/test/libsolidity/Assembly.cpp b/test/libsolidity/Assembly.cpp
index 78fa7bcf..926e29fe 100644
--- a/test/libsolidity/Assembly.cpp
+++ b/test/libsolidity/Assembly.cpp
@@ -39,6 +39,7 @@
 #include <iostream>
 
 using namespace std;
+using namespace langutil;
 using namespace dev::eth;
 
 namespace dev
diff --git a/test/libsolidity/ErrorCheck.cpp b/test/libsolidity/ErrorCheck.cpp
index fba2c897..e1f48fb2 100644
--- a/test/libsolidity/ErrorCheck.cpp
+++ b/test/libsolidity/ErrorCheck.cpp
@@ -27,6 +27,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 
 namespace
diff --git a/test/libsolidity/ErrorCheck.h b/test/libsolidity/ErrorCheck.h
index c70a6645..c3a2f522 100644
--- a/test/libsolidity/ErrorCheck.h
+++ b/test/libsolidity/ErrorCheck.h
@@ -30,10 +30,10 @@ namespace dev
 {
 namespace solidity
 {
-bool searchErrorMessage(Error const& _err, std::string const& _substr);
+bool searchErrorMessage(langutil::Error const& _err, std::string const& _substr);
 /// Checks that all provided errors are of the given type and have a given substring in their
 /// description.
 /// If the expectations are not met, returns a nonempty description, otherwise an empty string.
-std::string searchErrors(ErrorList const& _errors, std::vector<std::pair<Error::Type, std::string>> const& _expectations);
+std::string searchErrors(langutil::ErrorList const& _errors, std::vector<std::pair<langutil::Error::Type, std::string>> const& _expectations);
 }
 }
diff --git a/test/libsolidity/GasMeter.cpp b/test/libsolidity/GasMeter.cpp
index 4887dd5b..61f16c0f 100644
--- a/test/libsolidity/GasMeter.cpp
+++ b/test/libsolidity/GasMeter.cpp
@@ -29,6 +29,7 @@
 #include <libsolidity/interface/SourceReferenceFormatter.h>
 
 using namespace std;
+using namespace langutil;
 using namespace dev::eth;
 using namespace dev::solidity;
 using namespace dev::test;
diff --git a/test/libsolidity/InlineAssembly.cpp b/test/libsolidity/InlineAssembly.cpp
index 3079e032..31d21490 100644
--- a/test/libsolidity/InlineAssembly.cpp
+++ b/test/libsolidity/InlineAssembly.cpp
@@ -36,6 +36,7 @@
 #include <memory>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SMTChecker.cpp b/test/libsolidity/SMTChecker.cpp
index 195004cb..13fcc5b4 100644
--- a/test/libsolidity/SMTChecker.cpp
+++ b/test/libsolidity/SMTChecker.cpp
@@ -25,6 +25,7 @@
 #include <string>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SemVerMatcher.cpp b/test/libsolidity/SemVerMatcher.cpp
index b2f4b3c2..2e147847 100644
--- a/test/libsolidity/SemVerMatcher.cpp
+++ b/test/libsolidity/SemVerMatcher.cpp
@@ -28,6 +28,7 @@
 #include <test/Options.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SolidityExecutionFramework.h b/test/libsolidity/SolidityExecutionFramework.h
index ab71a3e0..d43e994d 100644
--- a/test/libsolidity/SolidityExecutionFramework.h
+++ b/test/libsolidity/SolidityExecutionFramework.h
@@ -72,13 +72,13 @@ public:
 		m_compiler.setOptimiserSettings(m_optimize, m_optimizeRuns);
 		if (!m_compiler.compile())
 		{
-			auto scannerFromSourceName = [&](std::string const& _sourceName) -> solidity::Scanner const& { return m_compiler.scanner(_sourceName); };
+			auto scannerFromSourceName = [&](std::string const& _sourceName) -> langutil::Scanner const& { return m_compiler.scanner(_sourceName); };
 			SourceReferenceFormatter formatter(std::cerr, scannerFromSourceName);
 
 			for (auto const& error: m_compiler.errors())
 				formatter.printExceptionInformation(
 					*error,
-					(error->type() == Error::Type::Warning) ? "Warning" : "Error"
+					(error->type() == langutil::Error::Type::Warning) ? "Warning" : "Error"
 				);
 			BOOST_ERROR("Compiling contract failed");
 		}
diff --git a/test/libsolidity/SolidityExpressionCompiler.cpp b/test/libsolidity/SolidityExpressionCompiler.cpp
index 37183279..a68eb3df 100644
--- a/test/libsolidity/SolidityExpressionCompiler.cpp
+++ b/test/libsolidity/SolidityExpressionCompiler.cpp
@@ -33,6 +33,7 @@
 #include <test/Options.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SolidityNameAndTypeResolution.cpp b/test/libsolidity/SolidityNameAndTypeResolution.cpp
index 5ec010c7..75726027 100644
--- a/test/libsolidity/SolidityNameAndTypeResolution.cpp
+++ b/test/libsolidity/SolidityNameAndTypeResolution.cpp
@@ -33,6 +33,7 @@
 #include <string>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SolidityNatspecJSON.cpp b/test/libsolidity/SolidityNatspecJSON.cpp
index 45191ce1..d930f697 100644
--- a/test/libsolidity/SolidityNatspecJSON.cpp
+++ b/test/libsolidity/SolidityNatspecJSON.cpp
@@ -27,6 +27,8 @@
 #include <liblangutil/Exceptions.h>
 #include <libdevcore/Exceptions.h>
 
+using namespace langutil;
+
 namespace dev
 {
 namespace solidity
diff --git a/test/libsolidity/SolidityParser.cpp b/test/libsolidity/SolidityParser.cpp
index cf5461ba..3534dd5b 100644
--- a/test/libsolidity/SolidityParser.cpp
+++ b/test/libsolidity/SolidityParser.cpp
@@ -29,6 +29,7 @@
 #include <test/libsolidity/ErrorCheck.h>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SolidityScanner.cpp b/test/libsolidity/SolidityScanner.cpp
index 53ec0a4c..2d164ae3 100644
--- a/test/libsolidity/SolidityScanner.cpp
+++ b/test/libsolidity/SolidityScanner.cpp
@@ -24,6 +24,7 @@
 #include <boost/test/unit_test.hpp>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SolidityTypes.cpp b/test/libsolidity/SolidityTypes.cpp
index 6f9d4ce8..c839afd4 100644
--- a/test/libsolidity/SolidityTypes.cpp
+++ b/test/libsolidity/SolidityTypes.cpp
@@ -26,6 +26,7 @@
 #include <boost/test/unit_test.hpp>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libsolidity/SyntaxTest.cpp b/test/libsolidity/SyntaxTest.cpp
index 91d1681f..45d32b55 100644
--- a/test/libsolidity/SyntaxTest.cpp
+++ b/test/libsolidity/SyntaxTest.cpp
@@ -25,6 +25,7 @@
 #include <stdexcept>
 
 using namespace dev;
+using namespace langutil;
 using namespace solidity;
 using namespace dev::solidity::test;
 using namespace dev::solidity::test::formatting;
diff --git a/test/libsolidity/ViewPureChecker.cpp b/test/libsolidity/ViewPureChecker.cpp
index b7ea1efc..64e52604 100644
--- a/test/libsolidity/ViewPureChecker.cpp
+++ b/test/libsolidity/ViewPureChecker.cpp
@@ -28,6 +28,7 @@
 #include <tuple>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libyul/Common.cpp b/test/libyul/Common.cpp
index b351483e..8913483f 100644
--- a/test/libyul/Common.cpp
+++ b/test/libyul/Common.cpp
@@ -37,6 +37,7 @@
 #include <boost/test/unit_test.hpp>
 
 using namespace std;
+using namespace langutil;
 using namespace dev::yul;
 using namespace dev::solidity;
 
diff --git a/test/libyul/Common.h b/test/libyul/Common.h
index ee191494..390e214f 100644
--- a/test/libyul/Common.h
+++ b/test/libyul/Common.h
@@ -27,13 +27,17 @@
 #include <vector>
 #include <memory>
 
-namespace dev
-{
-namespace solidity
+namespace langutil
 {
 class Scanner;
 class Error;
 using ErrorList = std::vector<std::shared_ptr<Error const>>;
+}
+
+namespace dev
+{
+namespace solidity
+{
 namespace assembly
 {
 struct AsmAnalysisInfo;
@@ -44,7 +48,7 @@ namespace yul
 namespace test
 {
 
-void printErrors(solidity::ErrorList const& _errors, solidity::Scanner const& _scanner);
+void printErrors(langutil::ErrorList const& _errors, langutil::Scanner const& _scanner);
 std::pair<std::shared_ptr<solidity::assembly::Block>, std::shared_ptr<solidity::assembly::AsmAnalysisInfo>>
 parse(std::string const& _source, bool _yul = true);
 solidity::assembly::Block disambiguate(std::string const& _source, bool _yul = true);
diff --git a/test/libyul/Parser.cpp b/test/libyul/Parser.cpp
index 3a887176..4aa3dd5c 100644
--- a/test/libyul/Parser.cpp
+++ b/test/libyul/Parser.cpp
@@ -36,6 +36,7 @@
 #include <memory>
 
 using namespace std;
+using namespace langutil;
 
 namespace dev
 {
diff --git a/test/libyul/YulOptimizerTest.cpp b/test/libyul/YulOptimizerTest.cpp
index 57c4d7f0..6b2b81c3 100644
--- a/test/libyul/YulOptimizerTest.cpp
+++ b/test/libyul/YulOptimizerTest.cpp
@@ -21,6 +21,9 @@
 
 #include <test/Options.h>
 
+#include <liblangutil/ErrorReporter.h>
+#include <liblangutil/Scanner.h>
+
 #include <libyul/optimiser/BlockFlattener.h>
 #include <libyul/optimiser/VarDeclPropagator.h>
 #include <libyul/optimiser/Disambiguator.h>
@@ -41,12 +44,10 @@
 #include <libyul/optimiser/RedundantAssignEliminator.h>
 #include <libyul/optimiser/Suite.h>
 
-#include <liblangutil/Scanner.h>
 #include <libsolidity/inlineasm/AsmPrinter.h>
 #include <libsolidity/inlineasm/AsmParser.h>
 #include <libsolidity/inlineasm/AsmAnalysis.h>
 #include <libsolidity/interface/SourceReferenceFormatter.h>
-#include <liblangutil/ErrorReporter.h>
 
 #include <boost/test/unit_test.hpp>
 #include <boost/algorithm/string.hpp>
@@ -54,6 +55,7 @@
 #include <fstream>
 
 using namespace dev;
+using namespace langutil;
 using namespace dev::yul;
 using namespace dev::yul::test;
 using namespace dev::solidity;
diff --git a/test/libyul/YulOptimizerTest.h b/test/libyul/YulOptimizerTest.h
index 7db17ceb..d11ff8fb 100644
--- a/test/libyul/YulOptimizerTest.h
+++ b/test/libyul/YulOptimizerTest.h
@@ -19,14 +19,17 @@
 
 #include <test/libsolidity/TestCase.h>
 
+namespace langutil
+{
+class Scanner;
+class Error;
+using ErrorList = std::vector<std::shared_ptr<Error const>>;
+}
 
 namespace dev
 {
 namespace solidity
 {
-class Scanner;
-class Error;
-using ErrorList = std::vector<std::shared_ptr<Error const>>;
 namespace assembly
 {
 struct AsmAnalysisInfo;
@@ -58,7 +61,7 @@ private:
 	bool parse(std::ostream& _stream, std::string const& _linePrefix, bool const _formatted);
 	void disambiguate();
 
-	static void printErrors(std::ostream& _stream, solidity::ErrorList const& _errors, solidity::Scanner const& _scanner);
+	static void printErrors(std::ostream& _stream, langutil::ErrorList const& _errors, langutil::Scanner const& _scanner);
 
 	std::string m_source;
 	bool m_yul = false;
diff --git a/test/tools/yulopti.cpp b/test/tools/yulopti.cpp
index df5331f7..8bc807d4 100644
--- a/test/tools/yulopti.cpp
+++ b/test/tools/yulopti.cpp
@@ -19,15 +19,15 @@
  */
 
 #include <libdevcore/CommonIO.h>
+#include <liblangutil/ErrorReporter.h>
+#include <liblangutil/Scanner.h>
 #include <libsolidity/inlineasm/AsmAnalysis.h>
 #include <libsolidity/inlineasm/AsmAnalysisInfo.h>
-#include <liblangutil/Scanner.h>
 #include <libsolidity/parsing/Parser.h>
 #include <libsolidity/inlineasm/AsmData.h>
 #include <libsolidity/inlineasm/AsmParser.h>
 #include <libsolidity/inlineasm/AsmPrinter.h>
 #include <libsolidity/interface/SourceReferenceFormatter.h>
-#include <liblangutil/ErrorReporter.h>
 
 #include <libyul/optimiser/BlockFlattener.h>
 #include <libyul/optimiser/Disambiguator.h>
@@ -58,6 +58,7 @@
 
 using namespace std;
 using namespace dev;
+using namespace langutil;
 using namespace dev::solidity;
 using namespace dev::solidity::assembly;
 using namespace dev::yul;