llvm-project/clang/test/SemaObjCXX/blocks.mm

// RUN: %clang_cc1 -fsyntax-only -verify -fblocks %s
@protocol NSObject;

void bar(id(^)(void));
void foo(id <NSObject>(^objectCreationBlock)(void)) {
    return bar(objectCreationBlock); // expected-warning{{incompatible pointer types passing 'id<NSObject> (^)()' to parameter of type 'id (^)()'}}
}

void bar2(id(*)(void));
void foo2(id <NSObject>(*objectCreationBlock)(void)) {
    return bar2(objectCreationBlock); // expected-warning{{incompatible pointer types passing 'id<NSObject> (*)()' to parameter of type 'id (*)()'}}
}

void bar3(id(*)()); // expected-note{{candidate function}}
void foo3(id (*objectCreationBlock)(int)) {
    return bar3(objectCreationBlock); // expected-error{{no matching}}
}

void bar4(id(^)()); // expected-note{{candidate function}}
void foo4(id (^objectCreationBlock)(int)) {
    return bar4(objectCreationBlock); // expected-error{{no matching}}
}

void foo5(id (^x)(int)) {
  if (x) { }
}

// <rdar://problem/6590445>
@interface Foo {
    @private
    void (^_block)(void);
}
- (void)bar;
@end

namespace N {
  class X { };      
  void foo(X);
}

@implementation Foo
- (void)bar {
    _block();
    foo(N::X()); // okay
}
@end

typedef signed char BOOL;
void foo6(void *block) {  
	void (^vb)(id obj, int idx, BOOL *stop) = (void (^)(id, int, BOOL *))block;
    BOOL (^bb)(id obj, int idx, BOOL *stop) = (BOOL (^)(id, int, BOOL *))block;
}

// <rdar://problem/8600419>: Require that the types of block
// parameters are complete.
namespace N1 {
  template<class _T> class ptr; // expected-note{{template is declared here}}

  template<class _T>
    class foo {
  public:
    void bar(void (^)(ptr<_T>));
  };

  class X;

  void test2();

  void test()
  {
    foo<X> f;
    f.bar(^(ptr<X> _f) { // expected-error{{implicit instantiation of undefined template 'N1::ptr<N1::X>'}}
        test2();
      });
  }
}