[asan] Relax a flaky invalid-pointer-pairs test

[zaks.anna]

Summary

This test is flaky. Specifically, on some Mac configurations we see the __sanitizer_ptr_cmp as the 0th frame. Let's relax it to not require that f is in frame #0.

61396==ERROR: AddressSanitizer: invalid-pointer-pair: 0x01e00510 0x01e004d0

#0 0x18f5a3 in __sanitizer_ptr_cmp ... libclang_rt.asan_osx_dynamic.dylib+0xaf5a3)
#1 0xdd924 in f(char, char*, char*) ... invalid-pointer-pairs.cc:14:14

[filcab]

LGTM.

Do you have any idea why we get this difference? Would be nice to know, and possibly to account for.

Thank you,

Filipe

[zaks.anna]

Do you have any idea why we get this difference? Would be nice to know, and possibly to account for.

Unfortunately, I don't know. I do know that we call llvm-symbolizer in both cases, so it's either the inconsitancy in that or the debug info.

[kubamracek]

In D21588#464443, @filcab wrote:

Do you have any idea why we get this difference? Would be nice to know, and possibly to account for.

This is due to INLINE on CheckForInvalidPointerPair. The function doesn’t get inlined in Debug builds, and the inlining is not even guaranteed for Release builds. If we never need the __sanitizer_ptr_cmp frame, we should use ALWAYS_INLINE, which seems to resolve the issue as well.

test/asan/TestCases/invalid-pointer-pairs.cc

 // RUN: %clangxx_asan -O0 %s -o %t -mllvm -asan-detect-invalid-pointer-pair
 
 // RUN: %env_asan_opts=detect_invalid_pointer_pairs=1 %run %t k 2>&1 | FileCheck %s -check-prefix=OK -allow-empty
 // RUN: %env_asan_opts=detect_invalid_pointer_pairs=1 not %run %t g 2>&1 | FileCheck %s -check-prefix=CMP -check-prefix=ALL-ERRORS
 // RUN: %env_asan_opts=detect_invalid_pointer_pairs=1 not %run %t s 2>&1 | FileCheck %s -check-prefix=SUB -check-prefix=ALL-ERRORS
 // RUN: %env_asan_opts=detect_invalid_pointer_pairs=1 not %run %t f 2>&1 | FileCheck %s -check-prefix=FREE -check-prefix=ALL-ERRORS
 
 #include <assert.h>
 #include <stdlib.h>
 
 int f(char c, char *p, char *q) {
   // ALL-ERRORS: ERROR: AddressSanitizer: invalid-pointer-pair
   // [[PTR1:0x[0-9a-f]+]] [[PTR2:0x[0-9a-f]+]]
   switch (c) {
   case 'g':
-    // CMP: #0 {{.*}} in f({{char, char\*, char\*|char,char \*,char \*}}) {{.*}}invalid-pointer-pairs.cc:[[@LINE+1]]:14
+    // CMP: #{{[0-9]+ .*}} in f({{char, char\*, char\*|char,char \*,char \*}}) {{.*}}invalid-pointer-pairs.cc:[[@LINE+1]]:14
     return p > q;
   case 's':
-    // SUB: #0 {{.*}} in f({{char, char\*, char\*|char,char \*,char \*}}) {{.*}}invalid-pointer-pairs.cc:[[@LINE+1]]:14
+    // SUB: #{{[0-9]+ .*}} in f({{char, char\*, char\*|char,char \*,char \*}}) {{.*}}invalid-pointer-pairs.cc:[[@LINE+1]]:14
     return p - q;
   case 'k': {
     // OK-NOT: ERROR
     char *p2 = p + 20;
     return p > p2;
   }
   case 'f': {
     char *p3 = p + 20;
     free(p);
-    // FREE: #0 {{.*}} in f({{char, char\*, char\*|char,char \*,char \*}}) {{.*}}invalid-pointer-pairs.cc:[[@LINE+2]]:14
+    // FREE: #{{[0-9]+ .*}} in f({{char, char\*, char\*|char,char \*,char \*}}) {{.*}}invalid-pointer-pairs.cc:[[@LINE+2]]:14
     // FREE: freed by thread
     return p < p3;
   }
   }
   assert(0);
 }
 
 int main(int argc, char **argv) {
   char *p = (char *)malloc(42);
   char *q = (char *)malloc(42);
   assert(argc >= 2);
   f(argv[1][0], p, q);
   free(p);
   free(q);
 }