Bug 497704

Summary:	>=sys-devel/llvm-3.4 - gcc runtime detection patch missing
Product:	Gentoo Linux	Reporter:	Philipp <carlphilippreh>
Component:	[OLD] Development	Assignee:	Bernard Cafarelli <voyageur>
Status:	RESOLVED FIXED
Severity:	normal	CC:	mgorny
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Philipp 2014-01-10 12:33:29 UTC

With llvm-3.3-r1, clang uses the gcc version set in /etc/env.d/gcc/config-*, but as of llvm-3.3-r2, this has stopped working and now clang uses whichever installed gcc version it finds (which is a gcc-4.9 snapshot for me that isn't supported by clang). As I understand, the build process has been reworked to use cmake instead of make as of llvm-3.3-r2 but I'm still not sure what triggered this change. I'll keep investigating but maybe someone here can spot the problem more quickly.

Comment 1 Michał Górny archtester

2014-01-10 14:32:49 UTC

-r2 was removed on 6 Jan :). -r3 should have this fixed, please try that one and let me know if it works for you.

Comment 2 Philipp 2014-01-10 14:52:40 UTC

The corresponding patch was dropped again in 3.4. Reapplying it fixes the problem. I never got around to test 3.3-r3, sorry about that.

Comment 3 Michał Górny archtester

2014-01-10 15:07:59 UTC

Do you mean clang-3.1-gentoo-runtime-gcc-detection-v3.patch? I thought it was fixed upstream. If it isn't, we should do something about it ;/.

Comment 4 Philipp 2014-01-10 15:11:35 UTC

Yes, that's the patch I'm talking about. What exactly should have been fixed upstream? As I understand, this patch is very gentoo-specific.

Comment 5 Michał Górny archtester

2014-01-10 15:17:12 UTC

Well, yes. But on the other hand, AFAIR the whole gcc installation issue is very distro-specific and upstream already carries code for various distros including Gentoo. It's just that their Gentoo code is not exactly correct :).

Alternatively we could try to find out why Gentoo needs that special handling and try to fix gcc wrapping to not have to patch clang. Not sure if it's feasible or even our fault.

Anyway, I'll readd the patch soon enough along with fix for bug #497620.

Comment 6 Michał Górny archtester

2014-01-10 17:25:40 UTC

+  10 Jan 2014; Michał Górny <mgorny@gentoo.org> llvm-3.4.ebuild:
+  Re-add missing runtime gcc detection patch, bug #497704.

Maybe we should apply it to -9999 as well?