Merge pull request #9007 from a3d4/fix-8727-no-return-optimizer-error

Report an error if immutables not assigned

test/libsolidity/SyntaxTest.cpp

@@ -74,7 +74,19 @@ void SyntaxTest::parseAndAnalyze()
 		try
 		{
 			if (!compiler().compile())
-				BOOST_THROW_EXCEPTION(runtime_error("Compilation failed even though analysis was successful."));
+			{
+				ErrorList const& errors = compiler().errors();
+				auto codeGeneretionErrorCount = count_if(errors.cbegin(), errors.cend(), [](auto const& error) {
+					return error->type() == Error::Type::CodeGenerationError;
+				});
+				auto errorCount = count_if(errors.cbegin(), errors.cend(), [](auto const& error) {
+					return error->type() != Error::Type::Warning;
+				});
+				// failing compilation after successful analysis is a rare case,
+				// it assumes that errors contain exactly one error, and the error is of type Error::Type::CodeGenerationError
+				if (codeGeneretionErrorCount != 1 || errorCount != 1)
+					BOOST_THROW_EXCEPTION(runtime_error("Compilation failed even though analysis was successful."));
+			}
 		}
 		catch (UnimplementedFeatureError const& _e)
 		{

test/libsolidity/syntaxTests/immutable/no_assignments.sol

@@ -0,0 +1,13 @@
+contract C {
+    uint immutable x;
+    constructor() {
+        x = 0;
+        while (true)
+        {}
+    }
+    function f() external view returns(uint) { return x; }
+}
+// ====
+// optimize-yul: true
+// ----
+// CodeGenerationError 1284: Some immutables were read from but never assigned, possibly because of optimization.