Pandas BUG: Warning when compiling pandas/_libs/algos.c

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• [X] I have confirmed this bug exists on the latest version of pandas.

• [X] I have confirmed this bug exists on the main branch of pandas.

Reproducible Example

Build pandas from commit b162331554d7c7f6fd46ddde1ff3908f2dc8bcce and review build logs

Issue Description

gcc -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -DOPENSSL_NO_SSL3 -fPIC -DNPY_NO_DEPRECATED_API=0 -Ipandas/_libs/include -I/home/ijtaba/.pyenv/versions/pandas-dev/lib/python3.9/site-packages/numpy/core/include -I/home/ijtaba/.pyenv/versions/pandas-dev/include -I/home/ijtaba/.pyenv/versions/3.9.10/include/python3.9 -c pandas/_libs/algos.c -o build/temp.linux-x86_64-3.9/pandas/_libs/algos.o
    In file included from pandas/_libs/algos.c:1270:
    pandas/_libs/include/pandas/vendored/klib/khash_python.h: In function ‘traced_realloc’:
    pandas/_libs/include/pandas/vendored/klib/khash_python.h:39:7: warning: pointer ‘old_ptr’ may be used after ‘realloc’ [-Wuse-after-free]
       39 |       PyTraceMalloc_Untrack(KHASH_TRACE_DOMAIN, (uintptr_t)old_ptr);
          |       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    pandas/_libs/include/pandas/vendored/klib/khash_python.h:36:15: note: call to ‘realloc’ here
       36 |   void *ptr = realloc(old_ptr, size);
          |               ^~~~~~~~~~~~~~~~~~~~~~

Expected Behavior

No warnings

Installed Versions

0+untagged.35052.g5db4dd6

Comment From: wooseogchoi

take

Comment From: rhshadrach

I am not seeing the warning when building main. Is it possible the standard install with meson doesn't show them?

Comment From: mroeschke

Agreed this is working on main and CI so without any additional information going to close