Merge lp:~brice-dobry/gcc-linaro/4.7-fma into lp:gcc-linaro/4.7

[Brice Dobry]

These changes are a backport from the mainline to support fma. The following are the two related blueprints:
  https://launchpad.net/gcc-linaro/+spec/backport-the-fma-intrinsic
  https://launchpad.net/gcc-linaro/+spec/fused-multiply-add-support
The testsuite changes are not included in this changeset.

[Linaro Toolchain Builder (cbuild)]

cbuild has taken a snapshot of this branch at r115046 and queued it for build.

The diff against the ancestor r115041 is available at:
 http://cbuild.validation.linaro.org/snapshots/gcc-linaro-4.7+bzr115046~brice-dobry~4.7-fma.diff

and will be built on the following builders:
 a9-builder a9hf-builder armv5-builder i686 x86_64 xaarch64 xaarch64_bare xcortexa15hf

You can track the build queue at:
 http://cbuild.validation.linaro.org/helpers/scheduler

cbuild-snapshot: gcc-linaro-4.7+bzr115046~brice-dobry~4.7-fma
cbuild-ancestor: lp:gcc-linaro+bzr115041
cbuild-state: check

[Yvan Roux (yvan-roux)]

* Diff matches upstream
* One failure on cortexa15 in libstdc++ : related to Qemu threading support
* Other targets are clean

review: Approve