[Bug libstdc++/85812] [7/8/9 Regression] make_exception_ptr can leak the allocated exception if construction throws

["redi at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85812

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
      Known to work|                            |6.4.0
   Target Milestone|---                         |7.4
            Summary|make_exception_ptr can leak |[7/8/9 Regression]
                   |the allocated exception if  |make_exception_ptr can leak
                   |construction throws         |the allocated exception if
                   |                            |construction throws
      Known to fail|                            |7.3.0, 8.1.0, 9.0

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Testcase:

#include <exception>

struct E {
    E() = default;
    E(const E&) { throw 1; }
};

int main()
{
  std::make_exception_ptr(E{});
}

=================================================================
==23465==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 129 byte(s) in 1 object(s) allocated from:
    #0 0x7f0ae56eb2d0 in __interceptor_malloc
/home/jwakely/src/gcc/gcc-7/libsanitizer/asan/asan_malloc_linux.cc:62
    #1 0x7f0ae531f8cf in __cxa_allocate_exception
/home/jwakely/src/gcc/gcc-7/libstdc++-v3/libsupc++/eh_alloc.cc:272
    #2 0x400d5f in main /tmp/ex.cc:10
    #3 0x7f0ae499af29 in __libc_start_main (/lib64/libc.so.6+0x20f29)

SUMMARY: AddressSanitizer: 129 byte(s) leaked in 1 allocation(s).


This started with 7.1 due to r239664 for Bug 68297