1// RUN: %clang_cc1 -analyze -analyzer-checker=core -analyzer-store=region -analyzer-constraints=range %s -verify 2// expected-no-diagnostics 3 4//===-- unions-region.m ---------------------------------------------------===// 5// 6// This file tests the analyzer's reasoning about unions. 7// 8//===----------------------------------------------------------------------===// 9 10// [testA] When using RegionStore, this test case previously had a 11// false positive of a 'pass-by-value argument is uninitialized' 12// warning at the call to 'testA_aux' and 'testA_aux_2'. 13union u_testA { 14 unsigned i; 15 float f; 16}; 17 18float testA(float f) { 19 int testA_aux(unsigned x); 20 int testA_aux_2(union u_testA z); 21 22 union u_testA swap; 23 swap.f = f; 24 25 if (testA_aux(swap.i)) // no-warning 26 swap.i = ((swap.i & 0xffff0000) >> 16) | ((swap.i & 0x0000fffff) << 16); 27 28 testA_aux_2(swap); // no-warning 29 30 return swap.f; 31} 32 33// [testB] When using RegionStore, this test case previously had a 34// false positive of a 'pass-by-value argument is uninitialized' 35// warning at the call to 'testB_aux'. 36void testB(int i) { 37 void testB_aux(short z); 38 union { short x[2]; unsigned y; } val; 39 val.y = 10; 40 testB_aux(val.x[1]); // no-warning 41} 42 43