1 // Test that out-of-scope local variables are ignored by LSan.
2 // RUN: LSAN_BASE="report_objects=1:use_registers=0:use_stacks=1"
3 // RUN: %clangxx_lsan %s -o %t
4 // RUN: LSAN_OPTIONS=$LSAN_BASE not %run %t 2>&1 | FileCheck %s
5 // RUN: LSAN_OPTIONS=$LSAN_BASE":exitcode=0" %run %t 2>&1 | FileCheck --check-prefix=CHECK-sanity %s
6
7 #include <stdio.h>
8 #include <stdlib.h>
9
10 void **pp;
11
12 // Put pointer far enough on the stack that LSan has space to run in without
13 // overwriting it.
14 // Hopefully the argument p will be passed on a register, saving us from false
15 // negatives.
16 __attribute__((noinline))
PutPointerOnStaleStack(void * p)17 void *PutPointerOnStaleStack(void *p) {
18 void *locals[2048];
19 locals[0] = p;
20 pp = &locals[0];
21 fprintf(stderr, "Test alloc: %p.\n", locals[0]);
22 return 0;
23 }
24
main()25 int main() {
26 PutPointerOnStaleStack(malloc(1337));
27 return 0;
28 }
29
30 // This must run after LSan, to ensure LSan didn't overwrite the pointer before
31 // it had a chance to see it. If LSan is invoked with atexit(), this works.
32 // Otherwise, we need a different method.
33 __attribute__((destructor))
34 __attribute__((no_sanitize_address))
ConfirmPointerHasSurvived()35 void ConfirmPointerHasSurvived() {
36 fprintf(stderr, "Value after LSan: %p.\n", *pp);
37 }
38 // CHECK: Test alloc: [[ADDR:.*]].
39 // CHECK-sanity: Test alloc: [[ADDR:.*]].
40 // CHECK: LeakSanitizer: detected memory leaks
41 // CHECK: [[ADDR]] (1337 bytes)
42 // CHECK: SUMMARY: {{(Leak|Address)}}Sanitizer:
43 // CHECK-sanity: Value after LSan: [[ADDR]].
44