Fix handling of local assembly variables in ReferencesResolver

libsolidity/analysis/ReferencesResolver.cpp

@@ -56,6 +56,7 @@ bool ReferencesResolver::visit(Block const& _block)
  if (!m_resolveInsideCode)
  return false;
  m_resolver.setScope(&_block);
+ m_localAssemblyVariables.push({});
  return true;
 }
 
@@ -65,6 +66,7 @@ void ReferencesResolver::endVisit(Block const& _block)
  return;
 
  m_resolver.setScope(_block.scope());
+ m_localAssemblyVariables.pop();
 }
 
 bool ReferencesResolver::visit(TryCatchClause const& _tryCatchClause)
@@ -364,14 +366,19 @@ void ReferencesResolver::operator()(yul::Identifier const& _identifier)
  else if (declarations.size() == 0)
  {
  if (
- boost::algorithm::ends_with(_identifier.name.str(), "_slot") ||
- boost::algorithm::ends_with(_identifier.name.str(), "_offset")
+ (
+ boost::algorithm::ends_with(_identifier.name.str(), "_slot") ||
+ boost::algorithm::ends_with(_identifier.name.str(), "_offset")
+ ) &&
+ m_localAssemblyVariables.top().count(_identifier.name.str()) == 0
  )
+ {
  m_errorReporter.declarationError(
  9467_error,
  nativeLocationOf(_identifier),
  "Identifier not found. Use \".slot\" and \".offset\" to access storage variables."
  );
+ }
  return;
  }
  if (auto var = dynamic_cast<VariableDeclaration const*>(declarations.front()))
@@ -396,10 +403,9 @@ void ReferencesResolver::operator()(yul::VariableDeclaration const& _varDecl)
  solAssert(nativeLocationOf(identifier) == originLocationOf(identifier), "");
  validateYulIdentifierName(identifier.name, nativeLocationOf(identifier));
 
- if (
- auto declarations = m_resolver.nameFromCurrentScope(identifier.name.str());
- !declarations.empty()
- )
+ m_localAssemblyVariables.top().insert(identifier.name.str());
+
+ if (auto declarations = m_resolver.nameFromCurrentScope(identifier.name.str()); !declarations.empty())
  {
  SecondarySourceLocation ssl;
  for (auto const* decl: declarations)

libsolidity/analysis/ReferencesResolver.h

@@ -30,6 +30,8 @@
 
 #include <list>
 #include <map>
+#include <set>
+#include <stack>
 
 namespace solidity::langutil
 {
@@ -101,6 +103,8 @@ class ReferencesResolver: private ASTConstVisitor, private yul::ASTWalker
  langutil::EVMVersion m_evmVersion;
  /// Stack of function definitions.
  std::vector<FunctionDefinition const*> m_functionDefinitions;
+ // Stack of sets to track local assembly variables and their scopes
+ std::stack<std::set<std::string>> m_localAssemblyVariables;
  bool const m_resolveInsideCode;
 
  InlineAssemblyAnnotation* m_yulAnnotation = nullptr;

test/libsolidity/syntaxTests/inlineAssembly/local_variable_old.sol

@@ -0,0 +1,13 @@
+contract C {
+ fallback() external {
+ assembly {
+ let x_offset := 0
+ let x_slot := 0
+ {
+ x_offset := 1
+ x_slot := 1
+ }
+ }
+ }
+}
+// ----

test/libsolidity/syntaxTests/inlineAssembly/local_variable_old_shadow.sol

@@ -0,0 +1,15 @@
+contract C {
+ fallback() external {
+ assembly {
+ let x_offset := 0
+ let x_slot := 0
+ {
+ let x_offset := 1
+ let x_slot := 1
+ }
+ }
+ }
+}
+// ----
+// DeclarationError 1395: (146-163): Variable name x_offset already taken in this scope.
+// DeclarationError 1395: (180-195): Variable name x_slot already taken in this scope.