1// RUN: %clangxx_msan -O2 %s -o %t && %run %t
2
3#include <sanitizer/msan_interface.h>
4
5struct S {
6  S(int a0) : a(a0) {}
7  int a;
8  int b;
9};
10
11// Here S is passed to FooRun as a 64-bit integer.
12// This triggers an optimization where 10000 * s.a is transformed into
13// ((*(uint64_t *)&s) * (10000 * 2**32)) >> 32
14// Test that MSan understands that this kills the uninitialized high half of S
15// (i.e. S::b).
16void FooRun(S s) {
17  int64_t x = 10000 * s.a;
18  __msan_check_mem_is_initialized(&x, sizeof(x));
19}
20
21int main(void) {
22  S z(1);
23  // Take &z to ensure that it is built on stack.
24  S *volatile p = &z;
25  FooRun(z);
26  return 0;
27}
28