compiler-rt/test/msan/select_origin.cpp

   1 // RUN: %clangxx_msan -fsanitize-memory-track-origins -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s
   2 // RUN: %clangxx_msan -fsanitize-memory-track-origins -O1 %s -o %t && not %run %t 2>&1 | FileCheck %s
   3 // RUN: %clangxx_msan -fsanitize-memory-track-origins -O2 %s -o %t && not %run %t 2>&1 | FileCheck %s
   4
   5 // Test condition origin propagation through "select" IR instruction.
   6
   7 #include <stdio.h>
   8 #include <stdint.h>
   9
  10 __attribute__((noinline))
  11 int *max_by_ptr(int *a, int *b) {
  12   return *a < *b ? b : a;
  13 }
  14
  15 int main(void) {
  16   int x;
  17   int *volatile px = &x;
  18   int y = 43;
  19   int *p = max_by_ptr(px, &y);
  20   // CHECK: Uninitialized value was created by an allocation of 'x' in the stack frame
  21   return *p;
  22 }