From 3e20f087d1a6f78779ee47f3552cc1b99d5b7fdd Mon Sep 17 00:00:00 2001 From: Eli Schwartz Date: Tue, 22 Nov 2022 22:56:10 -0500 Subject: [PATCH] python module: stop using distutils "link to libpython" probe on recent python On python >=3.8, this information is expected to be encoded in the sysconfig vars. In distutils, it is always necessary to link to libpython on Windows; for posix platforms, it depends on the value of LIBPYTHON (which is the library to link to, possibly the empty string) as generated by configure.ac and embedded into python.pc and python-config.sh, and then coded a second time in the distutils python sources. There are a couple of caveats which have ramifications for Cygwin and Android: - python.pc and python-config.sh disagree with distutils when python is not built shared. In that case, the former act the same as a shared build, while the latter *never* links to libpython - python.pc disagrees with python-config.sh and distutils when python is built shared. The former never links to libpython, while the latter do The disagreement is resolved in favor of distutils' behavior in all cases, and python.pc is correct for our purposes on python 3.12; see: https://github.com/python/cpython/pull/100356 https://github.com/python/cpython/pull/100967 Although it was not backported to older releases, Cygwin at least has always patched in a fix for python.pc, which behavior is now declared canonical. We can reliably assume it is always correct. This is the other half of the fix for #7702 --- mesonbuild/scripts/python_info.py | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/mesonbuild/scripts/python_info.py b/mesonbuild/scripts/python_info.py index e62bf0e40661..6be4a6546d45 100755 --- a/mesonbuild/scripts/python_info.py +++ b/mesonbuild/scripts/python_info.py @@ -64,10 +64,15 @@ def get_install_paths(): paths, install_paths = get_install_paths() def links_against_libpython(): - from distutils.core import Distribution, Extension - cmd = Distribution().get_command_obj('build_ext') - cmd.ensure_finalized() - return bool(cmd.get_libraries(Extension('dummy', []))) + # on versions supporting python-embed.pc, this is the non-embed lib + if sys.version_info >= (3, 8): + variables = sysconfig.get_config_vars() + return bool(variables.get('LIBPYTHON', 'yes')) + else: + from distutils.core import Distribution, Extension + cmd = Distribution().get_command_obj('build_ext') + cmd.ensure_finalized() + return bool(cmd.get_libraries(Extension('dummy', []))) variables = sysconfig.get_config_vars() variables.update({'base_prefix': getattr(sys, 'base_prefix', sys.prefix)})