Python 2 libpython symlink not created correctly on Cygwin

[embray]

#23781 introduced a regression that the symlink from lib/python2.7/config/libpython2.7.dll.a to lib/libpython2.7.dll.a is not created properly.

On Python 3 this "config" directory name is formatted "config-<PYTHON_LDVERSION>" whereas on Python 2 it should be just "config".

This prevents extension modules from linking to the correct libpython2.7 on Cygwin.

CC: @EmmanuelCharpentier

Component: porting: Cygwin

Keywords: windows cygwin python2

Author: Erik Bray

Branch/Commit: 9873e64

Reviewer: Emmanuel Charpentier

Issue created by migration from https://trac.sagemath.org/ticket/24189

[embray]

comment:1

I have a patch for this already--I'm just testing to make sure it works.

[embray]

Changed keywords from none to windows cygwin python2

[embray]

Commit: 9873e64

[embray]

New commits:

9873e64

The path to lib/python/config does not contain the Python LD_VERSION on Python 2

[embray]

Author: Erik Bray

[embray]

Branch: u/embray/cygwin/ticket-24189

[EmmanuelCharpentier]

comment:3

On Windos 10 + "Fall Creators Update", sage8.0.rc0+#24121+#24189, cython compiles.

However, Sage does not compile : fpylll fails to build (consistently). See enclosed log.

[EmmanuelCharpentier]

failure to build fpyll.

[tscrim]

comment:4

Attachment: fpylll-0.3.0dev.log

Is your fpylll build fixed by #24191?

[EmmanuelCharpentier]

Reviewer: Emmanuel Charpentier

[EmmanuelCharpentier]

comment:5

Replying to @tscrim:

Is your fpylll build fixed by #24191?

Yes and no : fpylll compiles, but Sage does not build. I get an error at Sagelib's compilation :

[sagelib-8.1.rc0] gcc -I/usr/include/ncurses -fno-strict-aliasing -g -O2 -DNDEBU
G -g -fwrapv -O3 -Wall -Wno-unused -I/home/charpent/sage/local/lib/python2.7/sit
e-packages/cysignals -I/home/charpent/sage/local/include -I/home/charpent/sage/l
ocal/include/python2.7 -I/home/charpent/sage/local/lib/python2.7/site-packages/n
umpy/core/include -I/home/charpent/sage/src -I/home/charpent/sage/src/sage/ext -
Ibuild/cythonized -I/home/charpent/sage/local/include/python2.7 -c build/cythoni
zed/sage/graphs/graph_decompositions/fast_digraph.c -o build/temp.cygwin-2.9.0-x
86_64-2.7/build/cythonized/sage/graphs/graph_decompositions/fast_digraph.o -fno-
strict-aliasing -DCYTHON_CLINE_IN_TRACEBACK=1 -std=c99
[sagelib-8.1.rc0] error: command 'gcc' failed with exit status 1
[sagelib-8.1.rc0] make[3]: *** [Makefile:33: sage] Error 1
[sagelib-8.1.rc0] make[3] : on quitte le répertoire « /home/charpent/sage/src »

I think I'm bitten by #24192, which I'll try next. But, as far as I understand, that implies restarting with make distclean. That will be long.

positive review on this ticket as well as for #24197, which turns out to be a buplicate.

[embray]

comment:6

I don't think you need to do a make distclean but it will require rebuilding all of the sage library at least.

[vbraun]

Changed branch from u/embray/cygwin/ticket-24189 to 9873e64