python 3.9 package leaks CFLAGS into user packages via sysconfig

[Matthias Koeppe]

On Mon, Dec 27, 2021 at 5:27 PM Matthias Koeppe <mkoeppe@math.ucdavis.edu>
wrote:

> $ python3.9 -m sysconfig | grep CFLAGS
> CFLAGS = "-Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall
> -ggdb -O2 -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2
> -fstack-protector-strong --param=ssp-buffer-size=4 -DOPENSSL_NO_SSL3=1
> -I/usr/include/uuid/
> -fdebug-prefix-map=/pub/devel/python/python39/python39-3.9.9-1.x86_64/build=/usr/src/debug/python39-3.9.9-1
> -fdebug-prefix-map=/pub/devel/python/python39/python39-3.9.9-1.x86_64/src/Python-3.9.9=/usr/src/debug/python39-3.9.9-1
> -ggdb -O2 -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2
> -fstack-protector-strong --param=ssp-buffer-size=4 -DOPENSSL_NO_SSL3=1
> -I/usr/include/uuid/
> -fdebug-prefix-map=/pub/devel/python/python39/python39-3.9.9-1.x86_64/build=/usr/src/debug/python39-3.9.9-1
> -fdebug-prefix-map=/pub/devel/python/python39/python39-3.9.9-1.x86_64/src/Python-3.9.9=/usr/src/debug/python39-3.9.9-1"
>
> These flags will end up in builds of user Python packages with extensions
> via sysconfig/distutils.
> This should be fixed by putting the necessary flags for the Python build
> into CFLAGS_NODIST instead [...]
>

Thanks, Marco, for the python-3.9.9-3 test package.
It has been reported to work well for us (
https://trac.sagemath.org/ticket/33078#comment:34), solving the reported
problem.

Matthias