Cherry-pick upstream r252457

Cherry-pick upstream r252457

Add initial support for the MUSL C library.

Summary:
This patch adds the LIBCXX_LIBC_IS_MUSL cmake option to allow the
building of libcxx with the Musl C library. The option is necessary as
Musl does not provide any predefined macro in order to test for its
presence, like GLIBC. Most of the changes specify the correct path to
choose through the various #if/#else constructs in the locale code.

Depends on D13407.

Reviewers: mclow.lists, jroelofs, EricWF

Subscribers: jfb, tberghammer, danalbert, srhines, cfe-commits

Differential Revision: http://reviews.llvm.org/D13673

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@252457 91177308-0d34-0410-b5e6-96231b3b80d8

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4335
R=dschuff@chromium.org

Committed: https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-libcxx.git;a=commit;h=91a5433c0c5e891098987276f3c6e98fe5c1b86a

[Petr Hosek, 2015-11-12 23:03:47]

Description was changed from

==========
Cherry-pick upstream r252457

Add initial support for the MUSL C library.

Summary:
This patch adds the LIBCXX_LIBC_IS_MUSL cmake option to allow the
building of libcxx with the Musl C library. The option is necessary as
Musl does not provide any predefined macro in order to test for its
presence, like GLIBC. Most of the changes specify the correct path to
choose through the various #if/#else constructs in the locale code.

Depends on D13407.

Reviewers: mclow.lists, jroelofs, EricWF

Subscribers: jfb, tberghammer, danalbert, srhines, cfe-commits

Differential Revision: http://reviews.llvm.org/D13673

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@252457
91177308-0d34-0410-b5e6-96231b3b80d8

BUG=
==========

to

==========
Cherry-pick upstream r252457

Add initial support for the MUSL C library.

Summary:
This patch adds the LIBCXX_LIBC_IS_MUSL cmake option to allow the
building of libcxx with the Musl C library. The option is necessary as
Musl does not provide any predefined macro in order to test for its
presence, like GLIBC. Most of the changes specify the correct path to
choose through the various #if/#else constructs in the locale code.

Depends on D13407.

Reviewers: mclow.lists, jroelofs, EricWF

Subscribers: jfb, tberghammer, danalbert, srhines, cfe-commits

Differential Revision: http://reviews.llvm.org/D13673

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@252457
91177308-0d34-0410-b5e6-96231b3b80d8

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4335
R= dschuff@chromium.org
==========

[Petr Hosek, 2015-11-12 23:03:47]

phosek@chromium.org changed reviewers:
+ dschuff@chromium.org

[Petr Hosek, 2015-11-12 23:06:01]

PTAL, I haven't landed 1411403009 yet and I've just noticed that musl support
was added upstream so I think we should use this one instead. The only change
from the upstream version is the configuration; CMakeLists.txt for upstream
libcxx has diverged considerably from ours and they use CMake options to enable
musl support but we cannot easily incorporate that change without pulling in a
lot of other CMakeLists.txt changes, so I used the __musl__ macro instead as in
case of 1411403009, which is the idea used by musl maintainers themselves in
their libcxx patches.

[Derek Schuff, 2015-11-13 06:32:29]

On 2015/11/12 23:06:01, Petr Hosek wrote:
> PTAL, I haven't landed 1411403009 yet and I've just noticed that musl support
> was added upstream so I think we should use this one instead. The only change
> from the upstream version is the configuration; CMakeLists.txt for upstream
> libcxx has diverged considerably from ours and they use CMake options to
enable
> musl support but we cannot easily incorporate that change without pulling in a
> lot of other CMakeLists.txt changes, so I used the __musl__ macro instead as
in
> case of 1411403009, which is the idea used by musl maintainers themselves in
> their libcxx patches.

LGTM.

Hopefully once we stop having to build for OSX 10.6 we can revert some of the
complex differences from upstream in the libcxx build.

[Petr Hosek, 2016-02-06 02:00:39]

Description was changed from

==========
Cherry-pick upstream r252457

Add initial support for the MUSL C library.

Summary:
This patch adds the LIBCXX_LIBC_IS_MUSL cmake option to allow the
building of libcxx with the Musl C library. The option is necessary as
Musl does not provide any predefined macro in order to test for its
presence, like GLIBC. Most of the changes specify the correct path to
choose through the various #if/#else constructs in the locale code.

Depends on D13407.

Reviewers: mclow.lists, jroelofs, EricWF

Subscribers: jfb, tberghammer, danalbert, srhines, cfe-commits

Differential Revision: http://reviews.llvm.org/D13673

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@252457
91177308-0d34-0410-b5e6-96231b3b80d8

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4335
R= dschuff@chromium.org
==========

to

==========
Cherry-pick upstream r252457

Add initial support for the MUSL C library.

Summary:
This patch adds the LIBCXX_LIBC_IS_MUSL cmake option to allow the
building of libcxx with the Musl C library. The option is necessary as
Musl does not provide any predefined macro in order to test for its
presence, like GLIBC. Most of the changes specify the correct path to
choose through the various #if/#else constructs in the locale code.

Depends on D13407.

Reviewers: mclow.lists, jroelofs, EricWF

Subscribers: jfb, tberghammer, danalbert, srhines, cfe-commits

Differential Revision: http://reviews.llvm.org/D13673

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@252457
91177308-0d34-0410-b5e6-96231b3b80d8

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4335
R=dschuff@chromium.org

Committed:
https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-libcxx.git;a=...
==========

[Petr Hosek, 2016-02-06 02:00:40]

Committed patchset #4 (id:60001) manually as
91a5433c0c5e891098987276f3c6e98fe5c1b86a (presubmit successful).