Issue 28224: Compilation warnings on Windows: export 'PyInit_xx' specified multiple times (original) (raw)

Issue28224

Created on 2016-09-21 07:21 by vstinner, last changed 2022-04-11 14:58 by admin. This issue is now closed.

Messages (5)
msg277102 - (view)	Author: STINNER Victor (vstinner) *	Date: 2016-09-21 07:21
I like when a compilation has no warning, because it helps to notice useful warnings and real bugs. The compilation of Python 3.5 on Windows emits the following warnings on buildbots: xxmodule.obj : warning LNK4197: export 'PyInit_xx' specified multiple times; using first specification xxmodule.obj : warning LNK4197: export 'PyInit_xx' specified multiple times; using first specification xxmodule.obj : warning LNK4197: export 'PyInit_xx' specified multiple times; using first specification http://buildbot.python.org/all/builders/AMD64%20Windows8%203.5/builds/1120/steps/test/logs/warnings%20%283%29 http://buildbot.python.org/all/builders/AMD64%20Windows8%203.x/builds/2634/steps/test/logs/warnings%20%283%29
msg277103 - (view)	Author: STINNER Victor (vstinner) *	Date: 2016-09-21 07:24
It seems like the warnings come from test_distutils: ----------------- 0:05:09 [ 44/405] test_distutils failed (env changed) (38 sec) xxmodule.c xxmodule.obj : warning LNK4197: export 'PyInit_xx' specified multiple times; using first specification Creating library D:\Temp\tmp_crvgs9y\Debug\Temp\tmp_crvgs9y\xx_d.cp37-win_amd64.lib and object D:\Temp\tmp_crvgs9y\Debug\Temp\tmp_crvgs9y\xx_d.cp37-win_amd64.exp LINK : /LTCG specified but no code generation required; remove /LTCG from the link command line to improve linker performance foo.c Creating library D:\Temp\tmpnq__9cbm\tempt\Temp\tmpfv6uys06\foo_d.cp37-win_amd64.lib and object D:\Temp\tmpnq__9cbm\tempt\Temp\tmpfv6uys06\foo_d.cp37-win_amd64.exp LINK : /LTCG specified but no code generation required; remove /LTCG from the link command line to improve linker performance foo.c Creating library D:\Temp\tmpnq__9cbm\tempt\Temp\tmpfv6uys06\foo_d.cp37-win_amd64.lib and object D:\Temp\tmpnq__9cbm\tempt\Temp\tmpfv6uys06\foo_d.cp37-win_amd64.exp LINK : /LTCG specified but no code generation required; remove /LTCG from the link command line to improve linker performance xxmodule.c xxmodule.obj : warning LNK4197: export 'PyInit_xx' specified multiple times; using first specification Creating library D:\Temp\tmp8n1b1bh8\Debug\Temp\tmp8n1b1bh8\xx_d.cp37-win_amd64.lib and object D:\Temp\tmp8n1b1bh8\Debug\Temp\tmp8n1b1bh8\xx_d.cp37-win_amd64.exp LINK : /LTCG specified but no code generation required; remove /LTCG from the link command line to improve linker performance foo.c Creating library D:\Temp\tmpk47tprte\tempt\Temp\tmpe3sksr_y\foo_d.cp37-win_amd64.lib and object D:\Temp\tmpk47tprte\tempt\Temp\tmpe3sksr_y\foo_d.cp37-win_amd64.exp LINK : /LTCG specified but no code generation required; remove /LTCG from the link command line to improve linker performance foo.c Creating library D:\Temp\tmpk47tprte\tempt\Temp\tmpe3sksr_y\foo_d.cp37-win_amd64.lib and object D:\Temp\tmpk47tprte\tempt\Temp\tmpe3sksr_y\foo_d.cp37-win_amd64.exp LINK : /LTCG specified but no code generation required; remove /LTCG from the link command line to improve linker performance xxmodule.c xxmodule.obj : warning LNK4197: export 'PyInit_xx' specified multiple times; using first specification Creating library build\temp.win-amd64-3.7-pydebug\Debug\xx_d.cp37-win_amd64.lib and object build\temp.win-amd64-3.7-pydebug\Debug\xx_d.cp37-win_amd64.exp LINK : /LTCG specified but no code generation required; remove /LTCG from the link command line to improve linker performance D:\buildarea\3.x.bolen-windows8\build\build\test_python_3476>exit 1 D:\buildarea\3.x.bolen-windows8\build\build\test_python_3476>exit 0 ----------------- By the way, test_distutils failed because of "env changed" but the changed environment is not logged :-( See my related issue #27829 for the missing warning.
msg277116 - (view)	Author: Jeremy Kloth (jkloth) *	Date: 2016-09-21 09:23
This is a known bug when compiling 64-bit extension modules. http://bugs.python.org/issue9709 http://bugs.python.org/issue16779 http://bugs.python.org/issue20166
msg297096 - (view)	Author: STINNER Victor (vstinner) *	Date: 2017-06-28 01:02
> This is a known bug when compiling 64-bit extension modules. Oh ok. I will just close my issue in that case :-)
msg304755 - (view)	Author: Stefan Krah (skrah) *	Date: 2017-10-22 15:26
I know I closed #20166 myself, but could we revisit this? I'm now in favor of telling people to fix their modules.