Warn about unreachable code.

11 files changed, 105 insertions, 0 deletions

diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/comment_fine.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/comment_fine.sol
new file mode 100644
index 00000000..17119ca6
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/comment_fine.sol
@@ -0,0 +1,6 @@
+contract C {
+    function f() public pure {
+        return;
+        // unreachable comment
+    }
+}
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/constant_condition.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/constant_condition.sol
new file mode 100644
index 00000000..e00398bc
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/constant_condition.sol
@@ -0,0 +1,8 @@
+contract C {
+    function f() public pure {
+        if (false) {
+            return; // unreachable, but not yet detected
+        }
+        return;
+    }
+}
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/do_while_continue.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/do_while_continue.sol
new file mode 100644
index 00000000..363c53e1
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/do_while_continue.sol
@@ -0,0 +1,12 @@
+contract C {
+    function f() public pure {
+        do {
+            uint a = 42; a;
+            continue;
+            return; // this is unreachable
+        } while(false);
+        return; // this is still reachable
+    }
+}
+// ----
+// Warning: (119-126): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/double_return.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/double_return.sol
new file mode 100644
index 00000000..9b755347
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/double_return.sol
@@ -0,0 +1,8 @@
+contract C {
+    function f() public pure returns (uint) {
+        return 0;
+        return 0;
+    }
+}
+// ----
+// Warning: (85-93): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/double_revert.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/double_revert.sol
new file mode 100644
index 00000000..a6457e4f
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/double_revert.sol
@@ -0,0 +1,8 @@
+contract C {
+    function f() public pure {
+        revert();
+        revert();
+    }
+}
+// ----
+// Warning: (70-78): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/for_break.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/for_break.sol
new file mode 100644
index 00000000..496addb2
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/for_break.sol
@@ -0,0 +1,12 @@
+contract C {
+    function f() public pure {
+        for (uint a = 0; a < 1; a++) {
+            break;
+            uint b = 42; b;
+        }
+        return;
+    }
+}
+// ----
+// Warning: (76-79): Unreachable code.
+// Warning: (114-128): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/if_both_return.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/if_both_return.sol
new file mode 100644
index 00000000..3513b17d
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/if_both_return.sol
@@ -0,0 +1,12 @@
+contract C {
+    function f(bool c) public pure {
+        if (c) {
+            return;
+        } else {
+            return;
+        }
+        return; // unreachable
+    }
+}
+// ----
+// Warning: (142-149): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/revert.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/revert.sol
new file mode 100644
index 00000000..9bb6a41c
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/revert.sol
@@ -0,0 +1,8 @@
+contract C {
+    function f() public pure {
+        revert();
+        uint a = 0; a;
+    }
+}
+// ----
+// Warning: (70-83): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/revert_empty.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/revert_empty.sol
new file mode 100644
index 00000000..4c80c5ca
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/revert_empty.sol
@@ -0,0 +1,8 @@
+contract C {
+    function f() public pure {
+        revert();
+        for(int i = 0; i < 3; i++) { f(); }
+    }
+}
+// ----
+// Warning: (70-105): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/while_break.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/while_break.sol
new file mode 100644
index 00000000..2d1ddd4f
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/while_break.sol
@@ -0,0 +1,12 @@
+contract C {
+    function f() public pure {
+        uint a = 0;
+        while (a < 100) {
+            a++;
+            break;
+            a--;
+        }
+    }
+}
+// ----
+// Warning: (138-141): Unreachable code.
diff --git a/test/libsolidity/syntaxTests/controlFlow/unreachableCode/while_continue.sol b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/while_continue.sol
new file mode 100644
index 00000000..55f98f67
--- /dev/null
+++ b/test/libsolidity/syntaxTests/controlFlow/unreachableCode/while_continue.sol
@@ -0,0 +1,11 @@
+contract C {
+    function f() public pure {
+        while(true) {
+            continue;
+            return;
+        }
+        return; // this is unreachable as well, but currently undetected (needs to consider constant condition "true")
+    }
+}
+// ----
+// Warning: (100-107): Unreachable code.