Re: [PATCH] selftest/mm: fix pointer comparison in mremap_test

On Thu, Nov 06, 2025 at 12:18:57PM +0100, David Hildenbrand (Red Hat) wrote:

On 06.11.25 11:49, Ankit Khushwaha wrote:

...

Pointer arthemitic with 'void * addr' and 'unsigned long long dest_alignment' triggers following warning:

mremap_test.c:1035:31: warning: pointer comparison always evaluates to false [-Wtautological-compare] 1035 | if (addr + c.dest_alignment < addr) { | ^

typecasting 'addr' to 'unsigned long long' to fix pointer comparison.

With which compiler are you seeing this?

Hi David,

clang version 20.1.8 (Fedora 20.1.8-4.fc42) raised this warning.

To reproduce: make -C tools/testing/selftests/mm CC=clang

Thanks,