[PATCH roland/arm] ARM: Clean up EABI-related configury

[Joseph S. Myers]

On Thu, 3 Jul 2014, Roland McGrath wrote:

> Now that pre-EABI is no longer supported, new toolchains are starting to be
> built using tuples arm-linux* rather than arm-linux*eabi*.  e.g. Fedora's
> cross tools use arm-linux-gnu.

That's clearly a broken way to configure such tools. arm-linux-gnu has 
well-defined semantics (old-ABI) which aren't changed by some tools no 
longer supporting old-ABI; the semantics of any GNU triplet are meant to 
be stable over time.

> Also, there was a lopsided situation where sysdeps/arm/ already assume EABI
> stuff but configure was doing some of the EABI-related magic only for Linux
> configurations.  Now sysdeps/arm/{pre,}configure require, check for, and
> cater to, EABI support universally for any ARM configuration.
> 
> This makes a cross-build on Fedora for --host=arm-linux-gnu succeed where
> before it did not.
> 
> OK?

This is OK (minus the sysdeps/microblaze/nptl/tls.h change, which doesn't 
belong in this patch), on the general principle of preferring detection of 
how the compiler actually behaves to anything involving matching patterns 
on host triplets.

-- 
Joseph S. Myers
joseph@codesourcery.com