Build issue with python 3.13 and GCC14

[micwoj92]

Combination of these packages and build status:

	gcc 13	gcc 14
python 3.12	✔️	✔️
python 3.13	✔️	❌

This is due to 2 things:
This function was dropped in python 3.13, I think it is this change python/cpython#118203
GCC 14 changed this to error, with GCC 13 -Wimplicit-function-declaration is only a warning

checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking for ar... ar
checking for a BSD-compatible install... /usr/bin/install -c
checking whether make sets $(MAKE)... yes
checking for main in -lm... yes
checking for an ANSI C-conforming const... yes
checking your blood pressure... a bit high, but we can proceed
configure: checking whether apxs is available...
checking for apxs2... no
checking for apxs... /usr/bin/apxs
checking Apache version... 2.4.62
checking for Apache libexec directory... /usr/lib/httpd/modules
checking for Apache include directory... -I/usr/include/httpd
checking for --with-python... /usr/bin/python
checking for /usr/bin/python-config... yes
checking Python version... 3.13
checking for --with-mutex-dir... no
Using MUTEX_DIR /tmp
checking for --with-max-locks... no
Using 8 MAX_LOCKS.
checking for --with-flex... no
checking for flex... /usr/bin/flex
found /usr/bin/flex, we'll use this. Use --with-flex to specify another.
checking flex version... 2.6.4. Good
configure: creating ./config.status
config.status: creating Makefile
config.status: creating src/Makefile
config.status: creating Doc/Makefile
config.status: creating src/include/mod_python.h
config.status: creating test/Makefile
config.status: creating dist/setup.py
config.status: creating dist/Makefile
config.status: creating scripts/Makefile
config.status: creating scripts/mod_python
make[1]: Entering directory '/build/mod_python/src/mod_python-b068800c425e00ca447de8bbe664650fedaf3b4a/src'

Building mod_python.so.

/usr/bin/apxs -I/build/mod_python/src/mod_python-b068800c425e00ca447de8bbe664650fedaf3b4a/src/include -I/usr/include/python3.13 -I/usr/include/python3.13   -c mod_python.c _apachemodule.c requestobject.c tableobject.c util.c serverobject.c connobject.c filterobject.c hlist.c hlistobject.c finfoobject.c version.c include/_apachemodule.h  include/filterobject.h  include/hlist.h include/mod_python.h  include/psp_flex.h include/psp_parser.h include/requestobject.h include/tableobject.h include/connobject.h include/finfoobject.h include/hlistobject.h include/mp_version.h include/_pspmodule.h  include/psp_string.h  include/serverobject.h include/util.h -L/usr/lib -lpython3.13 -ldl  -lm   
/usr/share/apr-1/build/libtool --silent --mode=compile gcc -prefer-pic -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions -Wp,-D_FORTIFY_SOURCE=3 -Wformat -Werror=format-security -fstack-clash-protection -fcf-protection -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -g -ffile-prefix-map=/build/apache/src=/usr/src/debug/apache -flto=auto  -DLINUX -D_REENTRANT -D_GNU_SOURCE  -I/usr/include/httpd  -I/usr/include/apr-1   -I/usr/include/apr-1 -I/usr/include -I/build/mod_python/src/mod_python-b068800c425e00ca447de8bbe664650fedaf3b4a/src/include -I/usr/include/python3.13 -I/usr/include/python3.13  -c -o mod_python.lo mod_python.c && touch mod_python.slo
/usr/share/apr-1/build/libtool --silent --mode=compile gcc -prefer-pic -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions -Wp,-D_FORTIFY_SOURCE=3 -Wformat -Werror=format-security -fstack-clash-protection -fcf-protection -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -g -ffile-prefix-map=/build/apache/src=/usr/src/debug/apache -flto=auto  -DLINUX -D_REENTRANT -D_GNU_SOURCE  -I/usr/include/httpd  -I/usr/include/apr-1   -I/usr/include/apr-1 -I/usr/include -I/build/mod_python/src/mod_python-b068800c425e00ca447de8bbe664650fedaf3b4a/src/include -I/usr/include/python3.13 -I/usr/include/python3.13  -c -o _apachemodule.lo _apachemodule.c && touch _apachemodule.slo
_apachemodule.c: In function '_apache_module_init':
_apachemodule.c:857:5: error: implicit declaration of function '_PyImport_FixupExtensionObject' [-Wimplicit-function-declaration]
  857 |     _PyImport_FixupExtensionObject(m, name, name
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
apxs:Error: Command failed with rc=65536
.
make[1]: *** [Makefile:57: mod_python.so] Error 1
make[1]: Leaving directory '/build/mod_python/src/mod_python-b068800c425e00ca447de8bbe664650fedaf3b4a/src'
make: *** [Makefile:34: do_dso] Error 2

[grisha]

@micwoj92 thanks for reporting this! Just checking - were you planning to submit a fix, since it seems like you already got to the bottom of this issue?

[micwoj92]

I can only think of adding -Wno-error=implicit-function-declaration to CFLAGS, but I would consider this a bandaid, not a proper solution.