[Sema][ObjC] Check whether a variable has a definition, rather than
checking its storage class, when determining whether casting a C pointer
to an ObjC pointer is allowed.
This change allows casting variables whose declarations are directly
contained in a linkage specification to an ObjC pointer type. Those
variables are treated as if they contain the extern specifier for the
purpose of determining whether they are definitions or not.
rdar://problem/29249853
Differential Revision: https://reviews.llvm.org/D31673
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@299992 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 9003af0a2442571f26f2b53a8d19ee25450212ed)
diff --git a/lib/Sema/SemaExprObjC.cpp b/lib/Sema/SemaExprObjC.cpp
index e9d8ee0..ba490e4 100644
--- a/lib/Sema/SemaExprObjC.cpp
+++ b/lib/Sema/SemaExprObjC.cpp
@@ -3347,7 +3347,7 @@
if (isAnyRetainable(TargetClass) &&
isAnyRetainable(SourceClass) &&
var &&
- var->getStorageClass() == SC_Extern &&
+ !var->hasDefinition(Context) &&
var->getType().isConstQualified()) {
// In system headers, they can also be assumed to be immune to retains.
diff --git a/test/SemaObjCXX/arc-bridged-cast.mm b/test/SemaObjCXX/arc-bridged-cast.mm
index 55cdd3f..b5d5774 100644
--- a/test/SemaObjCXX/arc-bridged-cast.mm
+++ b/test/SemaObjCXX/arc-bridged-cast.mm
@@ -52,3 +52,19 @@
ref = (__bridge_retained CFAnnotatedObjectRef) CreateSomething();
ref = (__bridge_retained CFAnnotatedObjectRef) CreateNSString();
}
+
+struct __CFAnnotatedObject {
+} cf0;
+
+extern const CFAnnotatedObjectRef r0;
+extern const CFAnnotatedObjectRef r1 = &cf0;
+extern "C" const CFAnnotatedObjectRef r2;
+extern "C" const CFAnnotatedObjectRef r3 = &cf0;
+
+void testExternC() {
+ id obj;
+ obj = (id)r0;
+ obj = (id)r1; // expected-error{{cast of C pointer type 'CFAnnotatedObjectRef' (aka 'const __CFAnnotatedObject *') to Objective-C pointer type 'id' requires a bridged cast}} expected-note{{use __bridge to convert directly}} expected-note{{use __bridge_transfer to transfer ownership of a +1 'CFAnnotatedObjectRef'}}
+ obj = (id)r2;
+ obj = (id)r3; // expected-error{{cast of C pointer type 'CFAnnotatedObjectRef' (aka 'const __CFAnnotatedObject *') to Objective-C pointer type 'id' requires a bridged cast}} expected-note{{use __bridge to convert directly}} expected-note{{use __bridge_transfer to transfer ownership of a +1 'CFAnnotatedObjectRef'}}
+}
