From: Douglas Gregor <dgregor@apple.com>
Date: Thu, 20 Oct 2011 17:58:49 +0000 (+0000)
Subject: There's no point in marking a declaration invalid just because it
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=cb8f951deacd251d9b3a73dc65f341477e039de1;p=clang

There's no point in marking a declaration invalid just because it
shadows a template parameter. Complain about the shadowing (or not,
under -fms-extensions), but don't invalidate the declaration. Merely
forget about the template parameter declaration.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@142596 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index d932e8a30d..024d273437 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -3781,7 +3781,7 @@ public:
                                    TemplateTy &SuggestedTemplate,
                                    TemplateNameKind &SuggestedKind);
 
-  bool DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl);
+  void DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl);
   TemplateDecl *AdjustDeclIfTemplate(Decl *&Decl);
 
   Decl *ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis,
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index bccb63eede..eff21cb12b 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -3347,9 +3347,8 @@ Decl *Sema::HandleDeclarator(Scope *S, Declarator &D,
       Previous.getFoundDecl()->isTemplateParameter()) {
     // Maybe we will complain about the shadowed template parameter.
     if (!D.isInvalidType())
-      if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
-                                          Previous.getFoundDecl()))
-        D.setInvalidType();
+      DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
+                                      Previous.getFoundDecl());
 
     // Just pretend that we didn't see the previous declaration.
     Previous.clear();
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index bb867ed33e..f445e9ff5b 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -6492,9 +6492,7 @@ Decl *Sema::ActOnAliasDeclaration(Scope *S,
   // Warn about shadowing the name of a template parameter.
   if (Previous.isSingleResult() &&
       Previous.getFoundDecl()->isTemplateParameter()) {
-    if (DiagnoseTemplateParameterShadow(Name.StartLocation,
-                                        Previous.getFoundDecl()))
-      Invalid = true;
+    DiagnoseTemplateParameterShadow(Name.StartLocation,Previous.getFoundDecl());
     Previous.clear();
   }
 
@@ -9585,6 +9583,7 @@ Decl *Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) {
     if (PrevDecl->isTemplateParameter()) {
       // Maybe we will complain about the shadowed template parameter.
       DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
+      PrevDecl = 0;
     }
   }
 
diff --git a/lib/Sema/SemaTemplate.cpp b/lib/Sema/SemaTemplate.cpp
index 8bfcde6092..d39731b90c 100644
--- a/lib/Sema/SemaTemplate.cpp
+++ b/lib/Sema/SemaTemplate.cpp
@@ -420,12 +420,12 @@ Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
 /// that the template parameter 'PrevDecl' is being shadowed by a new
 /// declaration at location Loc. Returns true to indicate that this is
 /// an error, and false otherwise.
-bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
+void Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
   assert(PrevDecl->isTemplateParameter() && "Not a template parameter");
 
   // Microsoft Visual C++ permits template parameters to be shadowed.
   if (getLangOptions().MicrosoftExt)
-    return false;
+    return;
 
   // C++ [temp.local]p4:
   //   A template-parameter shall not be redeclared within its
@@ -433,7 +433,7 @@ bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) {
   Diag(Loc, diag::err_template_param_shadow)
     << cast<NamedDecl>(PrevDecl)->getDeclName();
   Diag(PrevDecl->getLocation(), diag::note_template_param_here);
-  return true;
+  return;
 }
 
 /// AdjustDeclIfTemplate - If the given decl happens to be a template, reset
@@ -528,9 +528,10 @@ Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis,
     NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc,
                                            LookupOrdinaryName,
                                            ForRedeclaration);
-    if (PrevDecl && PrevDecl->isTemplateParameter())
-      Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc,
-                                                           PrevDecl);
+    if (PrevDecl && PrevDecl->isTemplateParameter()) {
+      DiagnoseTemplateParameterShadow(ParamNameLoc, PrevDecl);
+      PrevDecl = 0;
+    }
   }
 
   SourceLocation Loc = ParamNameLoc;
@@ -652,9 +653,10 @@ Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
     NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(),
                                            LookupOrdinaryName,
                                            ForRedeclaration);
-    if (PrevDecl && PrevDecl->isTemplateParameter())
-      Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
-                                                           PrevDecl);
+    if (PrevDecl && PrevDecl->isTemplateParameter()) {
+      DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
+      PrevDecl = 0;
+    }
   }
 
   T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc());