Re: Preliminary 'wip-armhf' branch pushed

[John Darrington]

On Thu, Jan 01, 2015 at 02:11:19AM -0500, Mark H Weaver wrote:
     John Darrington <address@hidden> writes:
     
     > On Wed, Dec 31, 2014 at 06:40:23PM -0500, Mark H Weaver wrote:
     >      
     >      * You added "CFLAGS=-Wno-cast-qual" and "--disable-werror" for ARM 
in
     >        'gcc-configure-flags-for-triplet', which I thought was a bad idea 
and
     >        didn't belong there.
     >
     > Have you tried actually building GCC ?
     
     Yes, I've built several GCCs including gcc-final.  I've also
     successfully built the 'hello' package.
     
     > I found that without those, it failed to build.
     
     Perhaps the problem you ran into was fixed in GCC 4.8.4.

Yeah possibly. 
     
     >      * You patched gcc/config/arm/linux-eabi.h unnecessarily.
     >
     > Without that patch, GCC actually builds soft-float code, even though
     > you may have passed the --with-float=hard flag.  What bits of that
     > patch do you think are not necessary?
     
     All of it seems to be unnecessary, by experiment.  I've used the
     resulting GCC to compile the following test program:
     
     'foo' accepts the double arguments via registers and passes a double to
     sinh via registers.  I also checked a variant that simply returned a*b,
     and it was clearly returning the result via register as well.
     
     I think it's quite clear that this is using the hard-float ABI, no?

My results showed that simple binaries like that compiled (and ran) ok.  The 
problems arose when linking with
bigger projects.  I don't recall the details.  Have you tried building libc?  I 
suspect that is where the patch
will be needed.

J'


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