Re: [commit] Use -mabi=altivec for AltiVec tests

[Daniel Jacobowitz <drow@false.org>]

On Sun, Oct 21, 2007 at 02:35:02PM +0200, Ulrich Weigand wrote:
> Hello,
> 
> both altivec-abi.exp and altivec-regs.exp had a number of test cases
> failing because the test case source code was compiled without using
> the -mabi=altivec flag.  As GDB expects the inferior to use the 
> AltiVec ABI, we need to compile the test case accordingly ...
> 
> Committed to mainline.

I don't think this is a good idea.  -mabi=altivec is an ABI-changing
option; you're supposed to match the ABI of your system libraries.
It will work out OK in practice though since the stack alignment is
already large enough on powerpc-linux.

I committed a GCC HEAD patch several weeks ago to mark the vector ABI of
PowerPC object files.  I also posted a linker patch to propogate this
into linked objects and I have the matching patch to GDB to
auto-detect the correct ABI and support both in GDB.  That also
fixes this test.

Unfortunately the linker patch is hung up right now because it notices
this same dubious action (linking -mabi=altivec and -mabi=no-altivec
code) and warns about it.  That causes a bunch of GCC testcase
failures.  The GCC testcases in question use, but do not actually
need, -mabi=altivec; they just need a nasty bug in -maltivec
-mabi=no-altivec fixed and my patch for that didn't get any comments
:-(

Maybe I should commit the linker patch without the warning?

-- 
Daniel Jacobowitz
CodeSourcery