cannot build on NixOS due to undefined C functions in `ext_s4u`

On NixOS installing gssapi fails with some GCC errors "implicit declaration of function ‘gss_acquire_cred_impersonate_name’" and "implicit declaration of function ‘gss_add_cred_impersonate_name’" when compiling ext_s4u.c:

      gcc -fno-strict-overflow -Wsign-compare -DNDEBUG -g -O3 -Wall -fPIC -DPy_LIMITED_API=51052544 -Igssapi/raw -I/home/lp/.cache/pypoetry/virtualenvs/dipex-GkntI14x-py3.13/include -I/nix/store/qwb5ygz9k8gs5ql9bpxbrsrv12r1icgm-python3-3.13.12/include/python3.13 -c gssapi/raw/ext_s4u.c -o build/temp.linux-x86_64-cpython-313/gssapi/raw/ext_s4u.o -I/nix/store/9jsgjswa0jmgbwk3l8ha2dy45yr4dz62-krb5-1.22.1-dev/include
      gssapi/raw/ext_s4u.c: In function ‘__pyx_pf_6gssapi_3raw_7ext_s4u_acquire_cred_impersonate_name’:
      gssapi/raw/ext_s4u.c:3282:28: error: implicit declaration of function ‘gss_acquire_cred_impersonate_name’ [-Wimplicit-function-declaration]
       3282 |         __pyx_v_maj_stat = gss_acquire_cred_impersonate_name((&__pyx_v_min_stat), __pyx_v_impersonator_cred->raw_creds, __pyx_v_name->raw_name, __pyx_v_input_ttl, __pyx_v_desired_mechs, __pyx_v_c_usage, (&__pyx_v_creds), (&__pyx_v_actual_mechs), (&__pyx_v_actual_ttl));
            |                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      gssapi/raw/ext_s4u.c: In function ‘__pyx_pf_6gssapi_3raw_7ext_s4u_2add_cred_impersonate_name’:
      gssapi/raw/ext_s4u.c:3945:28: error: implicit declaration of function ‘gss_add_cred_impersonate_name’ [-Wimplicit-function-declaration]
       3945 |         __pyx_v_maj_stat = gss_add_cred_impersonate_name((&__pyx_v_min_stat), __pyx_v_raw_input_cred, __pyx_v_impersonator_cred->raw_creds, __pyx_v_name->raw_name, (&__pyx_v_mech->raw_oid), __pyx_v_c_usage, __pyx_v_input_initiator_ttl, __pyx_v_input_acceptor_ttl, (&__pyx_v_creds), (&__pyx_v_actual_mechs), (&__pyx_v_actual_initiator_ttl), (&__pyx_v_actual_acceptor_ttl));
            |                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      error: command '/run/current-system/sw/bin/gcc' failed with exit code 1

I have installed the gcc, krb5 and krb5.dev nix packages which should have all the necessary dependencies to build gssapi.

Steps to reproduce

• Run NixOS 25.11
• Add gcc, krb5 and krb5.dev to your system packages
• Enable dynamically linked libraries (needed to run Python): programs.nix-ld.enable = true;
• Rebuild
• Create and enter a virtual environment
• Run pip install gssapi

Bắt đầu bằng cách tái hiện lỗi cài đặt NixOS với các gói gcc, krb5 và krb5.dev được liệt kê, sau đó kiểm tra gssapi/raw/ext_s4u.c và các đầu vào build được pip install gssapi sử dụng. Xác nhận thay đổi bằng cách build lại thành công extension trên thiết lập NixOS đã nêu mà không có các lỗi hàm chưa được định nghĩa.