Bug 351622 – sys-apps/openrc disrespects CFLAGS when linking

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Nathan Phillip Brink (binki) (RETIRED) 2011-01-14 04:06:08 UTC]

This breaks, for example, compiling openrc with:
$ make CFLAGS=-m32
on an amd64 system.

[Comment 1 Nathan Phillip Brink (binki) (RETIRED) 2011-01-14 04:07:41 UTC]

Created attachment 259760 [details]
openrc-0.7.0-1-g882a4b7-build.log

An example of compilation failure due to disrespect of CFLAGS during linking.

[Comment 2 Nathan Phillip Brink (binki) (RETIRED) 2011-01-14 04:09:21 UTC]

Created attachment 259762 [details, diff]
openrc-CFLAGS-during-linking.patch

This commit fixes the issue for me.

[Comment 3 Michał Górny 2011-01-14 04:20:49 UTC]

This is the correct behavior -- CFLAGS are to be used only when actually compiling a file. In this particular case, I see that the compiler is only called to link the files, and thus it doesn't need to pass CFLAGS. This is what default make rules do [1].

Please fix your LDFLAGS instead.

[1] http://uw714doc.sco.com/cgi-bin/info2html?(make.info)Catalogue%2520of%2520Rules

[Comment 4 Nathan Phillip Brink (binki) (RETIRED) 2011-01-14 14:56:04 UTC]

I appeal to the higher courts! ;-) Just because implicit make rules don't do something doesn't mean a well-written buildsystem shouldn't do that. For example, I think that CFLAGS should pretty much unconditionally be passed to the compiler driver when it's called. Automake does this and it makes sense, especially when there is a distinction between CPPFLAGS, LDFLAGS, and CFLAGS in the first place. This is a pitifully small patch which can only fix things.

[Comment 5 Jory A. Pratt 2011-01-14 16:35:30 UTC]

I do not see the point here but I would like to hear from the rest of the team as to their thoughts on the issue.

[Comment 6 William Hubbs 2011-01-14 18:26:26 UTC]

Comment #3 is correct in that Make's default rules do not do this. Also,
it is technically correct that CFLAGS are for compiling and LDFLAGS are
for linking.

However, as pointed out in comment #4, automake/autoconf based build
systems do pass CFLAGS to the linker.

I can see this going either way. We could have him add -m32 to his
ldflags, or we can apply this patch, which I also agree is a trivial
patch, and make our build system behave more like automake in this
regard.

[Comment 7 Michał Górny 2011-01-14 21:02:34 UTC]

(In reply to comment #6)
> I can see this going either way. We could have him add -m32 to his
> ldflags, or we can apply this patch, which I also agree is a trivial
> patch, and make our build system behave more like automake in this
> regard.

Or finally migrate to autotools.

[Comment 8 SpanKY 2011-01-14 21:19:50 UTC]

patch is fine.  i'm OK with delaying the user-is-stupid debate to some other time and/or place.

[Comment 9 William Hubbs 2011-01-14 23:56:04 UTC]

This patch has been applied in git, commit a534b6.