compiler-rt/test/asan/TestCases/alloca_underflow_left.cpp

   1 // RUN: %clangxx_asan -O0 -mllvm -asan-instrument-dynamic-allocas %s -o %t
   2 // RUN: not %run %t 2>&1 | FileCheck %s
   3 //
   4
   5 #include <assert.h>
   6 #include <stdint.h>
   7
   8 __attribute__((noinline)) void foo(int index, int len) {
   9   volatile char str[len] __attribute__((aligned(32)));
  10   assert(!(reinterpret_cast<uintptr_t>(str) & 31L));
  11   str[index] = '1'; // BOOM
  12 // CHECK: ERROR: AddressSanitizer: dynamic-stack-buffer-overflow on address [[ADDR:0x[0-9a-f]+]]
  13 // CHECK: WRITE of size 1 at [[ADDR]] thread T0
  14 }
  15
  16 int main(int argc, char **argv) {
  17   foo(-1, 10);
  18   return 0;
  19 }