[Bug libstdc++/103481] New: asan and ubsan work correctly on windows with clang + compiler-rt, however, libstdc++ does not correctly support it

[unlvsur at live dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103481

            Bug ID: 103481
           Summary: asan and ubsan work correctly on windows with clang +
                    compiler-rt, however, libstdc++ does not correctly
                    support it
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: unlvsur at live dot com
  Target Milestone: ---

Created attachment 51902
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51902&action=edit
use -fsanitize=address,undefined with clang + GCC libstdc++ on windows

#include<vector>

int main()
{
#if defined(__has_feature)
#if __has_feature(address_sanitizer)
#endif
#endif
        std::vector<int> vec;
        vec.reserve(20);
        vec.push_back(20);
        vec[4]=5;
}

Since libstdc++ detects __SANITIZE_ADDRESS__ not #if
__has_feature(address_sanitizer),

notice that gcc doesn't have __has_feature macro.


-D_GLIBCXX_SANITIZE_STD_ALLOCATOR=1 -D_GLIBCXX_SANITIZE_VECTOR=1

D:\hg\fast_io\examples\0007.legacy>clang++ -o test test.cc -Ofast -std=c++20
-flto -march=native -I../../include -fuse-ld=lld
-D_GLIBCXX_SANITIZE_STD_ALLOCATOR=1 -D_GLIBCXX_SANITIZE_VECTOR=1
-fsanitize=address,undefined

D:\hg\fast_io\examples\0007.legacy>test
=================================================================
==33828==ERROR: AddressSanitizer: container-overflow on address 0x01ceffa06bd0
at pc 0x7ff6223d2b48 bp 0x007a6651f500 sp 0x007a6651f548

This could work without issues.

I suggest to add detection for both __SANITIZE_ADDRESS__ and 
#if defined(__has_feature)
#if __has_feature(address_sanitizer)
#endif
#endif

This is also exactly what libsanitizer is doing. 

https://github.com/gcc-mirror/gcc/blob/16e2427f50c208dfe07d07f18009969502c25dc8/libsanitizer/include/sanitizer/asan_interface.h

#if __has_feature(address_sanitizer) || defined(__SANITIZE_ADDRESS__)