[Bug middle-end/99098] invalid/missing -Wfree-nonheap-object warnings

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99098

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Peter Ross from comment #2)
> The following test case produces a -Wfree-nonheap-object false positive. I
> argue that the memory being free'd is heap memory. It is offset by one to
> accomodate the negative offset applied immediately after malloc.

Doing -1 on an allocated memory location is undefined because you can only have
the address of 0...size to be taken of the "object" according to the C
standard. So the warning might seem wrong but you have undefined code
happening.