1// RUN: %clang_cl_asan %Od %s %Fe%t
2// RUN: not %run %t 2>&1 | FileCheck %s
3
4#include <malloc.h>
5
6int main() {
7 char *buffer = (char*)realloc(ptr: 0, size: 42);
8 buffer[-1] = 42;
9 // CHECK: AddressSanitizer: heap-buffer-overflow on address [[ADDR:0x[0-9a-f]+]]
10 // CHECK: WRITE of size 1 at [[ADDR]] thread T0
11 // CHECK-NEXT: {{#0 .* main .*realloc_left_oob.cpp}}:[[@LINE-3]]
12 // CHECK: [[ADDR]] is located 1 bytes before 42-byte region
13 // CHECK: allocated by thread T0 here:
14 // CHECK-NEXT: {{#0 .* realloc }}
15 // CHECK: {{ #[1-2] .* main .*realloc_left_oob.cpp}}:[[@LINE-8]]
16 free(ptr: buffer);
17}
18

source code of compiler-rt/test/asan/TestCases/Windows/realloc_left_oob.cpp