static local variables with destructors don't require a global destructor

unless we're on a platform without __cxa_atexit (or use thereof has been
disabled).  This patch actually just disables the check completely for
static locals, but I've filed http://llvm.org/bugs/show_bug.cgi?id=8176 to
track the platform-specific fix.

llvm-svn: 114269

clang/lib/Sema/SemaDeclCXX.cpp

@@ -5519,7 +5519,8 @@ void Sema::FinalizeVarWithDestructor(VarDecl *VD, const RecordType *Record) {
                             << VD->getDeclName()
                             << VD->getType());
 
-    if (!VD->isInvalidDecl() && VD->hasGlobalStorage())
+    // TODO: this should be re-enabled for static locals by !CXAAtExit
+    if (!VD->isInvalidDecl() && VD->hasGlobalStorage() && !VD->isStaticLocal())
       Diag(VD->getLocation(), diag::warn_global_destructor);
   }
 }

clang/test/SemaCXX/warn-global-constructors.cpp

@@ -72,7 +72,7 @@ namespace test6 {
   struct A { ~A(); };
 
   void f1() {
-    static A a; // expected-warning {{global destructor}}
+    static A a;
   }
   void f2() {
     static A& a = *new A;
@@ -84,8 +84,14 @@ namespace pr8095 {
     int x;
     Foo(int x1) : x(x1) {}
   };
-
-  void bar() {
+  void foo() {
     static Foo a(0);
   }
+
+  struct Bar {
+    ~Bar();
+  };
+  void bar() {
+    static Bar b;
+  }
 }