Add implicit declarations of allocation functions when looking them up for
redeclaration, not just when looking them up for a use -- we need the implicit
declaration to appropriately check various properties of them (notably, whether
they're deleted).

llvm-svn: 200729
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index d102cdf..995898a 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -2304,11 +2304,14 @@
   // Determine whether the previous declaration was a definition,
   // implicit declaration, or a declaration.
   diag::kind PrevDiag;
+  SourceLocation OldLocation = Old->getLocation();
   if (Old->isThisDeclarationADefinition())
     PrevDiag = diag::note_previous_definition;
-  else if (Old->isImplicit())
+  else if (Old->isImplicit()) {
     PrevDiag = diag::note_previous_implicit_declaration;
-  else
+    if (OldLocation.isInvalid())
+      OldLocation = New->getLocation();
+  } else
     PrevDiag = diag::note_previous_declaration;
 
   // Don't complain about this if we're in GNU89 mode and the old function
@@ -2322,10 +2325,10 @@
       !canRedefineFunction(Old, getLangOpts())) {
     if (getLangOpts().MicrosoftExt) {
       Diag(New->getLocation(), diag::warn_static_non_static) << New;
-      Diag(Old->getLocation(), PrevDiag);
+      Diag(OldLocation, PrevDiag);
     } else {
       Diag(New->getLocation(), diag::err_static_non_static) << New;
-      Diag(Old->getLocation(), PrevDiag);
+      Diag(OldLocation, PrevDiag);
       return true;
     }
   }
@@ -2391,7 +2394,7 @@
       Diag(New->getLocation(), diag::err_regparm_mismatch)
         << NewType->getRegParmType()
         << OldType->getRegParmType();
-      Diag(Old->getLocation(), diag::note_previous_declaration);      
+      Diag(OldLocation, diag::note_previous_declaration);
       return true;
     }
 
@@ -2403,7 +2406,7 @@
   if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
     if (NewTypeInfo.getProducesResult()) {
       Diag(New->getLocation(), diag::err_returns_retained_mismatch);
-      Diag(Old->getLocation(), diag::note_previous_declaration);      
+      Diag(OldLocation, diag::note_previous_declaration);
       return true;
     }
     
@@ -2468,7 +2471,7 @@
                diag::err_member_def_does_not_match_ret_type) << New;
         else
           Diag(New->getLocation(), diag::err_ovl_diff_return_type);
-        Diag(Old->getLocation(), PrevDiag) << Old << Old->getType();
+        Diag(OldLocation, PrevDiag) << Old << Old->getType();
         return true;
       }
       else
@@ -2514,7 +2517,7 @@
         //       is a static member function declaration.
         if (OldMethod->isStatic() != NewMethod->isStatic()) {
           Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
-          Diag(Old->getLocation(), PrevDiag) << Old << Old->getType();
+          Diag(OldLocation, PrevDiag) << Old << Old->getType();
           return true;
         }
 
@@ -2538,7 +2541,7 @@
           Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
             << New << New->getType();
         }
-        Diag(Old->getLocation(), PrevDiag) << Old << Old->getType();
+        Diag(OldLocation, PrevDiag) << Old << Old->getType();
 
       // Complain if this is an explicit declaration of a special
       // member that was initially declared implicitly.
@@ -2611,10 +2614,10 @@
       // Check cautiously as the friend object kind isn't yet complete.
       if (New->getFriendObjectKind() != Decl::FOK_None) {
         Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
-        Diag(Old->getLocation(), PrevDiag);
+        Diag(OldLocation, PrevDiag);
       } else {
         Diag(New->getLocation(), diag::err_different_language_linkage) << New;
-        Diag(Old->getLocation(), PrevDiag);
+        Diag(OldLocation, PrevDiag);
         return true;
       }
     }
@@ -2751,7 +2754,7 @@
     // or 'printf', just warn about the incompatible redeclaration.
     if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
       Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
-      Diag(Old->getLocation(), diag::note_previous_builtin_declaration)
+      Diag(OldLocation, diag::note_previous_builtin_declaration)
         << Old << Old->getType();
 
       // If this is a global redeclaration, just forget hereafter
@@ -2772,7 +2775,7 @@
   }
 
   Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
-  Diag(Old->getLocation(), PrevDiag) << Old << Old->getType();
+  Diag(OldLocation, PrevDiag) << Old << Old->getType();
   return true;
 }