-Wshadow should only warn about parameter declarations when we're
entering a function or block definition, not on every single declaration.
Unfortunately we don't have previous-lookup results around when it's time
to make this decision, so we have to redo the lookup. The alternative is
to use delayed diagnostics.
llvm-svn: 99172
diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index b529e5b..25277e9 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -783,7 +783,8 @@
const LookupResult &Previous,
Scope *S);
void DiagnoseFunctionSpecifiers(Declarator& D);
- void DiagnoseShadow(Scope *S, Declarator &D, const LookupResult& R);
+ void CheckShadow(Scope *S, VarDecl *D, const LookupResult& R);
+ void CheckShadow(Scope *S, VarDecl *D);
NamedDecl* ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
QualType R, TypeSourceInfo *TInfo,
LookupResult &Previous, bool &Redeclaration);
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index f5f2f94..2b1ad0a 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -2405,7 +2405,7 @@
// Diagnose shadowed variables before filtering for scope.
if (!D.getCXXScopeSpec().isSet())
- DiagnoseShadow(S, D, Previous);
+ CheckShadow(S, NewVD, Previous);
// Don't consider existing declarations that are in a different
// scope and are out-of-semantic-context declarations (if the new
@@ -2458,19 +2458,16 @@
return NewVD;
}
-/// \brief Diagnose variable or built-in function shadowing.
+/// \brief Diagnose variable or built-in function shadowing. Implements
+/// -Wshadow.
///
-/// This method is called as soon as a NamedDecl materializes to check
-/// if it shadows another local or global variable, or a built-in function.
-///
-/// For performance reasons, the lookup results are reused from the calling
-/// context.
+/// This method is called whenever a VarDecl is added to a "useful"
+/// scope.
///
/// \param S the scope in which the shadowing name is being declared
/// \param R the lookup of the name
///
-void Sema::DiagnoseShadow(Scope *S, Declarator &D,
- const LookupResult& R) {
+void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) {
// Return if warning is ignored.
if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored)
return;
@@ -2524,6 +2521,14 @@
Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
}
+/// \brief Check -Wshadow without the advantage of a previous lookup.
+void Sema::CheckShadow(Scope *S, VarDecl *D) {
+ LookupResult R(*this, D->getDeclName(), D->getLocation(),
+ Sema::LookupOrdinaryName, Sema::ForRedeclaration);
+ LookupName(R, S);
+ CheckShadow(S, D, R);
+}
+
/// \brief Perform semantic checking on a newly-created variable
/// declaration.
///
@@ -3984,8 +3989,6 @@
II = 0;
D.SetIdentifier(0, D.getIdentifierLoc());
D.setInvalidType(true);
- } else {
- DiagnoseShadow(S, D, R);
}
}
}
@@ -4213,14 +4216,21 @@
// Check the validity of our function parameters
CheckParmsForFunctionDef(FD);
+ bool ShouldCheckShadow =
+ Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored;
+
// Introduce our parameters into the function scope
for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) {
ParmVarDecl *Param = FD->getParamDecl(p);
Param->setOwningFunction(FD);
// If this has an identifier, add it to the scope stack.
- if (Param->getIdentifier() && FnBodyScope)
+ if (Param->getIdentifier() && FnBodyScope) {
+ if (ShouldCheckShadow)
+ CheckShadow(FnBodyScope, Param);
+
PushOnScopeChains(Param, FnBodyScope);
+ }
}
// Checking attributes of current function definition
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index fe6f3b9..007d625 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -6905,13 +6905,21 @@
CurBlock->Params.size());
CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic);
ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo);
+
+ bool ShouldCheckShadow =
+ Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored;
+
for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(),
E = CurBlock->TheDecl->param_end(); AI != E; ++AI) {
(*AI)->setOwningFunction(CurBlock->TheDecl);
// If this has an identifier, add it to the scope stack.
- if ((*AI)->getIdentifier())
+ if ((*AI)->getIdentifier()) {
+ if (ShouldCheckShadow)
+ CheckShadow(CurBlock->TheScope, *AI);
+
PushOnScopeChains(*AI, CurBlock->TheScope);
+ }
}
// Check for a valid sentinel attribute on this block.