From 6bec78d58b2fa73939c9cc16543c14433f004d5a Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Tue, 7 Jul 2009 17:00:05 +0000
Subject: [PATCH] Tighten up the conditions under which we build an implicit
 function declaration for a builtin.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@74917 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaDecl.cpp               |  9 ++++++---
 test/Sema/implicit-builtin-redecl.c | 12 ++++++++++++
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index a1ab68ac2a..85210f049d 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1431,15 +1431,18 @@ Sema::HandleDeclarator(Scope *S, Declarator &D,
     if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
       /* Do nothing*/;
     else if (R->isFunctionType()) {
-      if (CurContext->isFunctionOrMethod())
+      if (CurContext->isFunctionOrMethod() ||
+          D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
         NameKind = LookupRedeclarationWithLinkage;
     } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern)
       NameKind = LookupRedeclarationWithLinkage;
+    else if (CurContext->getLookupContext()->isTranslationUnit() &&
+             D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
+      NameKind = LookupRedeclarationWithLinkage;
 
     DC = CurContext;
     PrevDecl = LookupName(S, Name, NameKind, true, 
-                          D.getDeclSpec().getStorageClassSpec() != 
-                            DeclSpec::SCS_static,
+                          NameKind == LookupRedeclarationWithLinkage,
                           D.getIdentifierLoc());
   } else { // Something like "int foo::x;"
     DC = computeDeclContext(D.getCXXScopeSpec());
diff --git a/test/Sema/implicit-builtin-redecl.c b/test/Sema/implicit-builtin-redecl.c
index cd99b54553..36513bafb0 100644
--- a/test/Sema/implicit-builtin-redecl.c
+++ b/test/Sema/implicit-builtin-redecl.c
@@ -12,3 +12,15 @@ void *calloc(int, int, int); // expected-warning{{incompatible redeclaration of
 void f1(void) { 
   calloc(0, 0, 0);
 }
+
+void f2() {
+  int index = 1;
+}
+
+static int index;
+
+int f3() {
+  return index << 2;
+}
+
+typedef int rindex;
\ No newline at end of file
-- 
2.40.0