Bug 725642

Summary:	crossdev's use of embedded profile for mingw breaks cmake
Product:	Gentoo Linux	Reporter:	Mark Harmstone <mark>
Component:	Current packages	Assignee:	Gentoo Crossdev team <crossdev>
Status:	RESOLVED INVALID
Severity:	normal	CC:	slyfox, vapier
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Mark Harmstone 2020-05-27 16:57:04 UTC

At the moment, x86_64-w64-mingw32-emerge doesn't work for a number of packages that use cmake (e.g. dev-cpp/nlohmann_json). Because CMAKE_SYSTEM_NAME gets set to "Linux" rather than "Windows", the WIN32 conditional variable doesn't function as expected.

The root cause of this is the symlink of /usr/x86_64-w64-mingw32/etc/portage/make.profile to /usr/portage/profiles/embedded, which has kernel_linux hardcoded in /usr/portage/profiles/embedded/use.force. The suggestion in the Wiki to set KERNEL="-linux Winnt" in make.conf doesn't work, and confuses cmake even further.

I suggest that we probably need a dedicated mingw profile, identical to embedded but with kernel_Winnt forced instead of kernel_linux, and that crossdev should symlink to this instead.

Reproducible: Always

Comment 1 Sergei Trofimovich (RETIRED) gentoo-dev

2020-05-27 22:08:25 UTC

KERNEL="-linux Winnt" in make.conf suggestion is probably incorrect. These should be profiles variables only.

Note that crossdev already creates a small profile overlay to account for the offset:

"""
$ for f in /usr/i686-w64-mingw32/etc/portage/profile/*; do echo "#$f"; cat $f; done

#/usr/i686-w64-mingw32/etc/portage/profile/make.defaults
ARCH="x86"
KERNEL="-linux Winnt"
ELIBC="mingw"
#/usr/i686-w64-mingw32/etc/portage/profile/package.provided
#/usr/i686-w64-mingw32/etc/portage/profile/use.force
-kernel_linux
kernel_Winnt
"""

Please provide example faulty build.log and ${CTARGET}-emerge --info. That would help me to reproduce it locally.

Comment 2 Mark Harmstone 2020-05-27 23:50:27 UTC

That file wasn't there for me, but when I cleaned the overlay and rebuilt it it showed up. Sorry for this, you've obviously fixed it already. Thanks for responding quickly.

Comment 3 Sergei Trofimovich (RETIRED) gentoo-dev

2020-05-28 06:51:08 UTC

No problem. Was probably fixed in https://gitweb.gentoo.org/proj/crossdev.git/commit/?id=393e1cd0c6d3ac81fa166bafe6065d42849f622c

Yeah, stale overlay metadata keeps biting users. We should probably add something to cross-emerge to suggest overlay's regeneration when major changes like that happen.