Diagnose parameter names that shadow the names of inherited fields under -Wshadow-field.

This addresses PR34120. Note, unlike GCC, we take into account the accessibility of the field when deciding whether to warn or not.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@346041 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 22 insertions, 14 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index bf15e25d62..f8068dd9c8 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -12366,6 +12366,13 @@ Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
         D.setInvalidType(true);
       }
     }
+
+    if (LangOpts.CPlusPlus) {
+      DeclarationNameInfo DNI = GetNameForDeclarator(D);
+      if (auto *RD = dyn_cast<CXXRecordDecl>(CurContext))
+        CheckShadowInheritedFields(DNI.getLoc(), DNI.getName(), RD,
+                                   /*DeclIsField*/ false);
+    }
   }
 
   // Temporarily put parameter variables in the translation unit, not
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 51a4090393..af4be999a1 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -2832,13 +2832,14 @@ static const ParsedAttr *getMSPropertyAttr(const ParsedAttributesView &list) {
   return nullptr;
 }
 
-// Check if there is a field shadowing.
-void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
-                                      DeclarationName FieldName,
-                                      const CXXRecordDecl *RD) {
-  if (Diags.isIgnored(diag::warn_shadow_field, Loc))
-    return;
-
+// Check if there is a field shadowing.

+void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,

+                                      DeclarationName FieldName,

+                                      const CXXRecordDecl *RD,

+                                      bool DeclIsField) {

+  if (Diags.isIgnored(diag::warn_shadow_field, Loc))

+    return;

+

   // To record a shadowed field in a base
   std::map<CXXRecordDecl*, NamedDecl*> Bases;
   auto FieldShadowed = [&](const CXXBaseSpecifier *Specifier,
@@ -2872,13 +2873,13 @@ void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
       continue;
     auto BaseField = It->second;
     assert(BaseField->getAccess() != AS_private);
-    if (AS_none !=
-        CXXRecordDecl::MergeAccess(P.Access, BaseField->getAccess())) {
-      Diag(Loc, diag::warn_shadow_field)
-        << FieldName << RD << Base;
-      Diag(BaseField->getLocation(), diag::note_shadow_field);
-      Bases.erase(It);
-    }
+    if (AS_none !=

+        CXXRecordDecl::MergeAccess(P.Access, BaseField->getAccess())) {

+      Diag(Loc, diag::warn_shadow_field)

+        << FieldName << RD << Base << DeclIsField;

+      Diag(BaseField->getLocation(), diag::note_shadow_field);

+      Bases.erase(It);

+    }

   }
 }