test/Analysis/misc-ps.m

// RUN: clang -checker-cfref --verify -fblocks %s

// Reduced test case from crash in <rdar://problem/6253157>
@class NSObject;
@interface A @end
@implementation A
- (void)foo:(void (^)(NSObject *x))block {
  if (!((block != ((void *)0)))) {}
}
@end

// Reduced test case from crash in PR 2796;
//  http://llvm.org/bugs/show_bug.cgi?id=2796

unsigned foo(unsigned x) { return __alignof__((x)) + sizeof(x); }

// Improvement to path-sensitivity involving compound assignments.
//  Addresses false positive in <rdar://problem/6268365>
//

unsigned r6268365Aux();

void r6268365() {
  unsigned x = 0;
  x &= r6268365Aux();
  unsigned j = 0;
    
  if (x == 0) ++j;
  if (x == 0) x = x / j; // no-warning
}

void divzeroassume(unsigned x, unsigned j) {  
  x /= j;  
  if (j == 0) x /= 0;     // no-warning
  if (j == 0) x /= j;     // no-warning
  if (j == 0) x = x / 0;  // no-warning
}

void divzeroassumeB(unsigned x, unsigned j) {  
  x = x / j;  
  if (j == 0) x /= 0;     // no-warning
  if (j == 0) x /= j;     // no-warning
  if (j == 0) x = x / 0;  // no-warning
}

// PR 2948 (testcase; crash on VisitLValue for union types)
// http://llvm.org/bugs/show_bug.cgi?id=2948

void checkaccess_union() {
  int ret = 0, status;
  if (((((__extension__ (((union {
    __typeof (status) __in; int __i;}
    )
    {
      .__in = (status)}
      ).__i))) & 0xff00) >> 8) == 1)
        ret = 1;
}

// InitListExpr processing

typedef float __m128 __attribute__((__vector_size__(16), __may_alias__));
__m128 return128() {
  // This compound literal has a Vector type.  We currently just
  // return UnknownVal.
  return __extension__(__m128) { 0.0f, 0.0f, 0.0f, 0.0f };
}

typedef long long __v2di __attribute__ ((__vector_size__ (16)));
typedef long long __m128i __attribute__ ((__vector_size__ (16), __may_alias__));
__m128i vec128i(long long __q1, long long __q0) {
  // This compound literal returns true for both isVectorType() and 
  // isIntegerType().
  return __extension__ (__m128i)(__v2di){ __q0, __q1 };
}

// Zero-sized VLAs.
void check_zero_sized_VLA(int x) {
  if (x)
    return;

  int vla[x]; // expected-warning{{VLAs with no elements have undefined behavior}}
}

void check_uninit_sized_VLA() {
  int x;
  int vla[x]; // expected-warning{{The expression used to specify the number of elements in the VLA 'vla' evaluates to an undefined or garbage value.}}
}