On Wed, Jun 10, 2020 at 04:27:27PM -0600, Jeff Law wrote:
> On Mon, 2019-07-22 at 12:39 -0400, Arvind Sankar wrote:
> > The gcc configure script does not use the config/picflag.m4 macro to
> > customize PICFLAG according to the host when using --enable-host-shared.
> >
> > Fix configure.ac to do so.
> >
> > Tested bootstrap on x86_64-linux-gnu.
> >
> > 2019-07-22 Arvind Sankar
> >
> > * gcc/configure.ac: Use GCC_PICFLAG.
> I know this is old
>
> Can you be more specific here about what you're trying to fix? ie, what
> host/target combination are you working on. What behavior are you seeing
> (presumably usage of -fPIC) what behavior did you expect (some other flag
> presumably).
>
> From looking at picflag.m4 the thing I worry the most about is the various
> ix86/x86_64 clauses which specify -fpic. It looks like your change would
> cause
> us to start using -fpic rather than -fPIC as we've been doing for eons and I
> worry that might have unintended consequences.
>
> Thanks,
> Jeff
> >
>
I don't remember exactly, but I don't think there was any actual
problem. At the time, I was playing around with trying to build the bulk
of cc1 etc as a shared library to reduce the size of the compiler
installation. IIRC I just came across this, noticed that there's a
config/picflag.m4 which wasn't getting used and posted this as a
cleanup.
This was originally added in r177967 ("Centralize PICFLAG
configuration") which used it for PICFLAG_FOR_TARGET (which still goes
via config/picflag.m4) but the host code which was added later just
hardcodes -fPIC.
