Re: [OE-core] [PATCH] Add -fcommon to BUILD_CFLAGS to a number of recipes

Richard Purdie
2020-05-03T10:04:44Z

On Sun, 2020-05-03 at 10:26 +0200, Daniel Mack wrote:
> When building on a gcc 10 enabled host distribution (such as Fedora
> 32),
> a number of recipies need explicit treatment to enable '-fcommon' in
> BUILD_CFLAGS. There might be more of those fixes needed.
>
> Commit 46827b8616 ("recipes: Use -fcommon explicitly") already
> addressed
> that for some places, but tweaking CFLAGS doesn't seem to suffice.

Thanks for this, its definitely something we need to fid.

The work in the previous patch was fixing gcc 10 target builds, not
host. Your patch changes CFLAGS to BUILD_CFLAGS in places which means
when we upgrade to gcc 10 things will break.

Basically:

CFLAGS should cover build and target
TARGET_CFLAGS should cover target builds (gcc cross as gcc 10)
BUILD_CFLAGS should cover host tools (gcc 10 on the host)

so the correct place should be CFLAGS which should cover target and
build (host).

Its possible that some recipes build native and target components in
which case they might use CFLAGS and BUILD_CFLAGS. Based on what you
say in the commit message, there might be a bug and we might be missing
injecting CFLAGS into BUILD_CFLAGS.

I think this is going to need a little more investigation to get it
right.

Cheers,

Richard