[Bug libstdc++/97659] Invalid pointer subtraction in vector::insert() (reported by pointer-subtract AddressSanitizer)

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97659

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2020-11-01
     Ever confirmed|0                           |1

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Alternatively, we could reinterpret_cast<uintptr_t> before doing the
subtractions (and divide the result by sizeof(_Tp)), which would avoid the
overhead of adjusting the ASan tracking.

Either way, if my assumption about the cause is right, it's not a real bug in
std::vector, it's caused by incorrect (or insufficient) ASan instrumentation.