Bug report

Bug description:

InPython/perf_jit_trampoline.c, theperf_map_jit_init function checks forNULL to detect mmap failures, but mmap() returnsMAP_FAILED (which is(void*)-1) on error, notNULL.

This means mmap failures are never detected, and jitdump initialization proceeds with an invalid pointer.

CPython versions tested on:

CPython main branch, 3.15, 3.14, 3.13

Operating systems tested on:

Linux

Linked PRs

• gh-144194: Fix mmap failure check in perf_jit_trampoline.c #143713