target/8520: -mips64 not forcing -mgp64 under mips*-*-linux* target

[jbr at keyresearch dot com]

>Number:         8520
>Category:       target
>Synopsis:       -mips64 not forcing -mgp64 under mips*-*-linux* target
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Nov 10 14:56:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Jeff Rubin
>Release:        3.2
>Organization:
>Environment:
Cross compiler running on i686-pc-linux running Red Hat 7.2
linux
>Description:
In config.gcc, for mips*-*-linux*, tm_file has near the end
linux.h and then mips/linux.h.  The first thing mips/linux.h
does is to include mips/mips.h.  So the header files come
in in the order ... linux.h mips/mips.h <rest of>linux.h
In mips/mips.h there is a macro definition for CC1_SPEC
which has the correct stuff to make -mips64 force -mgp64,
among other things.  However, it is conditionaled on
#ifndef CC1_SPEC.  linux.h also has a macro definition
for CC1_SPEC (setting it to %{profile:-p}) which is
conditionaled the same way.  Since linux.h comes before
mips.h, CC1_SPEC gets defined by linux.h and not by
mips.h.
>How-To-Repeat:

>Fix:
Partial fix: add #undef CC1_SPEC to mips/linux.h before the
#include "mips/mips.h" to undo the definition in linux.h.
I'm not sure how you would get the profile forces -p effect
back or even if you want to in this case.
>Release-Note:
>Audit-Trail:
>Unformatted: