Functions declared in a scope should not hide previous declaration in earlier scopes

[ogoffart]

Summary

This code should be an error:

void foo(int); 
void f3() {
  int foo(float);
  {
    float foo(int); // expected-error {{functions that differ only in their return type cannot be overloaded}}
  }
}

the foo(float) function declared at function scope should not hide the float(int) while trying to redeclare functions.

[ogoffart]

Ping.
This would be required for http://reviews.llvm.org/D19764

[rsmith]

lib/Sema/SemaLookup.cpp

1091

Please rename this to something like SearchNamespaceScope (and invert the sense of it) to reflect what it now means.

lib/Sema/SemaLookup.cpp

     bool Found = false;
     for (; I != IEnd && S->isDeclScope(*I); ++I) {
       if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
-        if (NameKind == LookupRedeclarationWithLinkage) {
-          // Determine whether this (or a previous) declaration is
-          // out-of-scope.
-          if (!LeftStartingScope && !Initial->isDeclScope(*I))
-            LeftStartingScope = true;
-
-          // If we found something outside of our starting scope that
-          // does not have linkage, skip it. If it's a template parameter,
+        if (NameKind == LookupRedeclarationWithLinkage &&
+            !(*I)->isTemplateParameter()) {
+          // If it's a template parameter,
           // we still find it, so we can diagnose the invalid redeclaration.
-          if (LeftStartingScope && !((*I)->hasLinkage()) &&
-              !(*I)->isTemplateParameter()) {
+
+          // Determine whether this (or a previous) declaration is
+          // out-of-scope.
+          if (!LeftStartingScope && !Initial->isDeclScope(*I))
+            LeftStartingScope = true;
+
+          // If we found something outside of our starting scope that
+          // does not have linkage, skip it.
+          if (LeftStartingScope && !((*I)->hasLinkage())) {
             R.setShadowed();
             continue;
           }
+        } else {
+          Found = true;
         }
-
-        Found = true;
         R.addDecl(ND);
       }
     }

test/SemaCXX/function-redecl.cpp

     void bar(int); // expected-note 2{{previous declaration is here}}
   }
 
-  void foo(int); // expected-note 2{{previous declaration is here}}
+  void foo(int); // expected-note 3{{previous declaration is here}}
 
   void f2() {
     int foo(int); // expected-error {{functions that differ only in their return type cannot be overloaded}}

       }
     }
   }
+
+  void f3() {
+    int foo(float);
+    {
+      float foo(int); // expected-error {{functions that differ only in their return type cannot be overloaded}}
+    }
+  }
 }
 
 class A {