| // RUN: %clangxx_msan -O2 %s -o %t && %run %t |
| |
| #include <sanitizer/msan_interface.h> |
| |
| struct S { |
| S(int a0) : a(a0) {} |
| int a; |
| int b; |
| }; |
| |
| // Here S is passed to FooRun as a 64-bit integer. |
| // This triggers an optimization where 10000 * s.a is transformed into |
| // ((*(uint64_t *)&s) * (10000 * 2**32)) >> 32 |
| // Test that MSan understands that this kills the uninitialized high half of S |
| // (i.e. S::b). |
| void FooRun(S s) { |
| int64_t x = 10000 * s.a; |
| __msan_check_mem_is_initialized(&x, sizeof(x)); |
| } |
| |
| int main(void) { |
| S z(1); |
| // Take &z to ensure that it is built on stack. |
| S *volatile p = &z; |
| FooRun(z); |
| return 0; |
| } |
