1 files changed, 96 insertions, 0 deletions
diff --git a/test/SemaObjC/block-type-safety.m b/test/SemaObjC/block-type-safety.m
new file mode 100644
index 0000000..dab0af4
--- /dev/null
+++ b/test/SemaObjC/block-type-safety.m
@@ -0,0 +1,96 @@
+// RUN: %clang_cc1 -fsyntax-only %s -verify -fblocks
+// test for block type safety.
+
+@interface Super  @end
+@interface Sub : Super @end
+
+void f2(void(^f)(Super *)) {
+    Super *o;
+    f(o);
+}
+
+void f3(void(^f)(Sub *)) {
+    Sub *o;
+    f(o);
+}
+
+void r0(Super* (^f)()) {
+     Super *o = f();
+}
+
+void r1(Sub* (^f)()) {
+    Sub *o = f();
+}
+
+@protocol NSObject;
+
+void r2 (id<NSObject> (^f) (void)) {
+  id o = f();
+}
+
+void test1() {
+    f2(^(Sub *o) { });    // expected-error {{incompatible block pointer types passing 'void (^)(Sub *)', expected 'void (^)(Super *)'}}
+    f3(^(Super *o) { });  // OK, block taking Super* may be called with a Sub*
+
+    r0(^Super* () { return 0; });  // OK
+    r0(^Sub* () { return 0; });    // OK, variable of type Super* gets return value of type Sub*
+    r0(^id () { return 0; });  // expected-error {{incompatible block pointer types passing 'id (^)(void)', expected 'Super *(^)()'}}
+
+    r1(^Super* () { return 0; });  // expected-error {{incompatible block pointer types passing 'Super *(^)(void)', expected 'Sub *(^)()'}}
+    r1(^Sub* () { return 0; });    // OK
+    r1(^id () { return 0; });      // expected-error {{incompatible block pointer types passing 'id (^)(void)', expected 'Sub *(^)()'}}
+     
+    r2(^id<NSObject>() { return 0; });
+}
+
+
+@interface A @end
+@interface B @end
+
+void f0(void (^f)(A* x)) {
+  A* a;
+  f(a);
+}
+
+void f1(void (^f)(id x)) {
+  B *b;
+  f(b);
+}
+
+void test2(void) 
+{ 
+  f0(^(id a) { }); // OK
+  f1(^(A* a) { }); // expected-error {{incompatible block pointer types passing 'void (^)(A *)', expected 'void (^)(id)'}}
+   f1(^(id<NSObject> a) { });	// OK
+}
+
+@interface NSArray
+   // Calls block() with every object in the array
+   -enumerateObjectsWithBlock:(void (^)(id obj))block;
+@end
+
+@interface MyThing
+-(void) printThing;
+@end
+
+@implementation MyThing
+    static NSArray* myThings;  // array of MyThing*
+
+   -(void) printThing {  }
+
+// programmer wants to write this:
+   -printMyThings1 {
+       [myThings enumerateObjectsWithBlock: ^(MyThing *obj) { // expected-error {{incompatible block pointer types sending 'void (^)(MyThing *)', expected 'void (^)(id)'}}
+           [obj printThing];
+       }];
+   }
+
+// strict type safety requires this:
+   -printMyThings {
+       [myThings enumerateObjectsWithBlock: ^(id obj) {
+           MyThing *obj2 = (MyThing *)obj;
+           [obj2 printThing];
+       }];
+   }
+@end
+