compiler-rt/test/msan/realloc-origin.cpp

   1 // RUN: %clangxx_msan -fsanitize-memory-track-origins -O0 %s -o %t && not %run %t >%t.out 2>&1
   2 // RUN: FileCheck %s < %t.out
   3 // RUN: %clangxx_msan -fsanitize-memory-track-origins -O2 %s -o %t && not %run %t >%t.out 2>&1
   4 // RUN: FileCheck %s < %t.out
   5
   6 // This test relies on realloc from 100 to 101 being done in-place.
   7
   8 #include <stdlib.h>
   9 int main(int argc, char **argv) {
  10   char *p = (char *)malloc(100);
  11   p = (char *)realloc(p, 101);
  12   char x = p[100];
  13   free(p);
  14   return x;
  15   // CHECK: WARNING: MemorySanitizer: use-of-uninitialized-value
  16   // CHECK: {{#0 0x.* in main .*realloc-origin.cpp:}}[[@LINE-2]]
  17
  18   // CHECK: Uninitialized value was created by a heap allocation
  19   // CHECK: {{#0 0x.* in .*realloc}}
  20   // CHECK: {{#1 0x.* in main .*realloc-origin.cpp:}}[[@LINE-9]]
  21 }