Re: py-libxml2 fails to build on Linux

["David H. Gutteridge" <david%gutteridge.ca@localhost>]

On Sun, 17 Mar 2024 at 11:20:15 +0100, Benny Siegert wrote:
> Hi!
>
> With an up-to-date pkgsrc, I am trying to build py-libxml2 on Linux 
> (Fedora 39), and it fails miserably:
>
> cc -Wsign-compare -DNDEBUG -O2 -I/usr/include -I/usr/pkg/include 
> -D_XOPEN_SOURCE_EXTENDED=1 -I/usr/pkg/include/ncurses 
> -I/usr/pkg/include/db4 -O2 -I/usr/include -I/usr/pkg/include 
> -D_XOPEN_SOURCE_EXTENDED=1 -I/usr/pkg/include/ncurses 
> -I/usr/pkg/include/db4 -O2 -I/usr/include -I/usr/pkg/include 
> -D_XOPEN_SOURCE_EXTENDED=1 -I/usr/pkg/include/ncurses 
> -I/usr/pkg/include/db4 -O2 -I/usr/include -I/usr/pkg/include/python3.11 
> -I/usr/pkg/include -I/usr/include -I/usr/pkg/include/python3.11 
> -I/usr/pkg/include -fPIC -D_REENTRANT=1 -I/usr/include/libxml2 
> -I/usr/pkg/include/python3.11 -c libxml2-py.c -o 
> build/temp.linux-aarch64-cpython-311/libxml2-py.o
>
> libxml2-py.c:206:1: error: unknown type name 'XML_POP_WARNINGS'
>  206 | XML_POP_WARNINGS
>      | ^~~~~~~~~~~~~~~~
>
> libxml2-py.c:210:10: error: expected '=', ',', ';', 'asm' or 
> '__attribute__' before '*' token
>
>  210 | PyObject *
>      |          ^
> libxml2-py.c:334:1: error: unknown type name 'XML_POP_WARNINGS'
>  334 | XML_POP_WARNINGS
>      | ^~~~~~~~~~~~~~~~
>
> libxml2-py.c:338:10: error: expected '=', ',', ';', 'asm' or 
> '__attribute__' before '*' token
>
>  338 | PyObject *
>      |          ^
>
> And many more errors.
>
> Looking at that compiler command line, it is definitely not using 
> buildlink, and notably it lists /usr/include before /usr/pkg/include. I 
> assume this means it is trying to compile against the libxml in Fedora 
> base, which is at a different version.
>
> FWIW, the libxml2 version in Fedora is libxml2-2.10.4-3.fc39.aarch64, 
> whereas the pkgsrc one is 2.12.4.
>
> Unfortunately, I know very little about python/C builds, anyone has a 
> hint for me?

Try setting PREFER_PKGSRC? (Either for libxml2 or just "yes" in 
general.)

It builds for me on Fedora 39, but I'm already configured a particular
way that avoids this kind of problem.

Regards,

Dave