Allow memory-safe inline assembly dialect flag.

libsolidity/analysis/DocStringTagParser.cpp

@@ -202,7 +202,17 @@ bool DocStringTagParser::visit(InlineAssembly const& _assembly)
 				if (valuesSeen.insert(value).second)
 				{
 					if (value == "memory-safe-assembly")
+					{
+						if (_assembly.annotation().markedMemorySafe)
+							m_errorReporter.warning(
+								8544_error,
+								_assembly.location(),
+								"Inline assembly marked as memory safe using both a NatSpec tag and an assembly flag. "
+								"If you are not concerned with backwards compatibility, only use the assembly flag, "
+								"otherwise only use the NatSpec tag."
+							);
 						_assembly.annotation().markedMemorySafe = true;
+					}
 					else
 						m_errorReporter.warning(
 							8787_error,

libsolidity/analysis/SyntaxChecker.cpp

@@ -334,6 +334,27 @@ bool SyntaxChecker::visit(UnaryOperation const& _operation)
 
 bool SyntaxChecker::visit(InlineAssembly const& _inlineAssembly)
 {
+	if (_inlineAssembly.flags())
+		for (auto flag: *_inlineAssembly.flags())
+		{
+			if (*flag == "memory-safe")
+			{
+				if (_inlineAssembly.annotation().markedMemorySafe)
+					m_errorReporter.syntaxError(
+						7026_error,
+						_inlineAssembly.location(),
+						"Inline assembly marked memory-safe multiple times."
+					);
+				_inlineAssembly.annotation().markedMemorySafe = true;
+			}
+			else
+				m_errorReporter.warning(
+					4430_error,
+					_inlineAssembly.location(),
+					"Unknown inline assembly flag: \"" + *flag + "\""
+				);
+		}
+
 	if (!m_useYulOptimizer)
 		return false;