Commit graph

9 commits

Author SHA1 Message Date
Dan Albert
3ce0769aa5 Only use <atomic> for C++11 and newer.
Any pre-C++11 clients of stdatomic.h that use libc++ are being forced
over to <atomic>, which they don't have the language support to use.

Change-Id: I62445c1f2541410a1569498c09433c7196635537
2014-10-16 07:52:51 -07:00
Hans Boehm
76ac4d0853 Make memory_order_acquire visible in global namespace
We were missing that using directive when including <atomic>.

Bug:17736764
Change-Id: Ie8ca92a952749415567bcd5fa21d56629a364660
2014-09-30 18:35:04 -07:00
Hans Boehm
32429606bf 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 00aaea3645 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
2014-08-29 17:03:26 -07:00
Elliott Hughes
e0c56efddf Use __GNUC_PREREQ rather than __GNUC_PREREQ__ to match glibc.
Bug: 16874785
Change-Id: I8512f8be3fd149d8720c5c3b4657bedd5ce2b1d1
2014-08-29 15:54:11 -07:00
Hans Boehm
3e4a0099a1 Undefine _Atomic before redefining
Stdatomic.h was potentially redefining _Atomic, in spite of a
prior definition by <atomic>.  This could cause g++ builds that
included <stdatomic.h> with an available <atomic> header to break.

Change-Id: I562c7115118c0587d594d4d5b62d25101e47bfd8
2014-08-26 15:58:15 -07:00
Hans Boehm
00aaea3645 Fix, generalize stdatomic.h; improve test.
We seem to use this stdatomic.h sometimes, and slightly different prebuilts
at other times, making them all difficult to test, and making it unclear
which one we're testing.  This generalizes the bionic header so that it
can be used directly as the prebuilt header as well.  So long as they
don't diverge again, that should somewhat improve test coverage.

Use the correct builtin for atomic_is_lock_free.

Fix atomic_flag_init.

Turn on atomic tests even with __GLIBC__, since they now appear to pass.

Include uchar.h in stdatomic.h where needed.

Add a basic memory ordering test.

Fix bit-rotted comments in bionic tests makefile.

Change-Id: If6a14c1075b379395ba5d93357d56025c0ffab68
2014-08-22 15:50:17 -07:00
Hans Boehm
019d395811 Have stdatomic.h punt to C++ atomic when possible
This is an alternate, somewhat simpler, fix that makes it safe to
include both <atomic> and <stdatomic.h> from C++ code in either order.
It means that C code consistently uses one implementation of atomics
and C++ another.  We still have to make sure that those two
implementations interoperate correctly at runtime; in particular,
any flavor of atomic object needs to be represented exactly like the
underlying type, with the proper alignment constraint.

Bug:17007799
Change-Id: Iffcfc5220d8fa150f89dd083a121b24d23f268fc
2014-08-15 10:38:20 -07:00
Hans Boehm
8b002362d9 Define atomic_charN_t only if charN_t is supported.
Some platform code is apparently compiled with switches that do
not support char16_t and char32_t.  This caused stdatomic.h to fail
to compile.  This CL makes stdatomic.h usable in those environments.

Change-Id: Ie5a17f20b8b545c97128d00605b4eabd2a6bfe3e
2014-07-16 17:31:05 -07:00
Elliott Hughes
e6c57fcb05 Add C11 <stdatomic.h>.
Bug: 14903517
Change-Id: I631dbfdaa698cf7fea8e3b5e18a32586383e62a5
2014-05-23 20:06:03 -07:00