tree 23d3f05c668cab59870dd136ad1f9cc1368c25eb
parent 2b10e2f12262c5ac5d8dac4f0bfc16b1848cbfec
author Hans Boehm <hboehm@google.com> 1409264492 -0700
committer Hans Boehm <hboehm@google.com> 1409683022 -0700

Make stdatomic.h work with gcc4.6 host compiler

This is needed to make L work correctly, and bionic tests pass
again, after applying the equivalent of
commit 00aaea364501b3b0abe58dae461136159df1e356 there.

It makes the preexisting code that uses __sync implementations
much more useful, although we should no longer be exercising that
code in AOSP.

Specifically fixes:

We were invoking __has_extension and __has_builtin for GCC compilations.
They're clang specific. Restructured the tests.

The __sync implementation was not defining the LOCK_FREE macros.

ATOMIC_VAR_INIT was using named field initializations.  These are a
C, not C++, feature, that is not supported by g++ 4.6.

The stdatomic bionic test still failed with 4.6 and glibc with our
questionable LOCK_FREE macro implementation.  Don't run that piece
with 4.6.

In L, this is a prerequisite for fixing:

    Bug:16880454
    Bug:16513433

Change-Id: I9b61e42307f96a114dce7552b6ead4ad1c544eab
(cherry picked from commit 32429606bf696d3b2ca555f132a0d60c566d0bd0)