Make function calls throw if target does not have code.

Low-level calls still just execute and will actually report "success".
This allows `x.call.value(y)()` for x being a non-contract account.

1 files changed, 7 insertions, 0 deletions

diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 1f93cf8c..e8350931 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -1517,6 +1517,13 @@ void ExpressionCompiler::appendExternalFunctionCall(
 		m_context << u256(0);
 	m_context << dupInstruction(m_context.baseToCurrentStackOffset(contractStackPos));
 
+	// Check the the target contract exists (has code) for non-low-level calls.
+	if (funKind == FunctionKind::External || funKind == FunctionKind::CallCode || funKind == FunctionKind::DelegateCall)
+	{
+		m_context << Instruction::DUP1 << Instruction::EXTCODESIZE << Instruction::ISZERO;
+		m_context.appendConditionalJumpTo(m_context.errorTag());
+	}
+
 	if (_functionType.gasSet())
 		m_context << dupInstruction(m_context.baseToCurrentStackOffset(gasStackPos));
 	else