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