This reverts commit 13aff21f0d,
since the CMake part relanded in c06a8f9caa.
The GN part is a bit simpler than last time due to the
prior simplifications in acea470c16.
We do ship those headers, so the directory name should not be something
that can potentially conflict with user-defined directories.
Differential Revision: https://reviews.llvm.org/D95956
- Merge 6706342f48 -- no more libcxx_needs_site_config, we now
always need it
- Since it was always off in practice, write_config bitrot. Unbitrot
it so that it works
- Remove copy step and let concat step write to final location
immediately -- and fix copy destination directory
As a side effect, libcxx/include/BUILD.gn now has only a single
sources list, which means the cmake sync script should be able to
automatically sync additions and removals of .h files. On the flipside,
this means this file now must be updated after most changes to
libcxx/include/__config_site.in, and looking through the last few months
of changes this looks like it's going to be a wash.
I noticed __availability was missing, so I manually diffed the
file lists and put all recently(ish) added headers:
* __availability from 2eadbc8614
* concepts from 601f763182
* execution from 0a06eb911b
* numbers from 4f6c4b473c
Also remove libcxx_install_support_headers like the CMake build did in
6706342f48, and unconditionally copy
support/win32/{limits_msvc_win32.h,locale_win32.h} like the CMake
build always did as far as I can tell.
37c030f81a made it so that depending on //libcxx/include
automatically added the copied header dir to the include search path.
For some reason, clang can't build against the copied libcxx headers
(it complains about ldiv_t not being a type). I don't have a mac
to debug right now, but for the clang target this change was
unintentional anyways -- only depend on the copies target, instead
of on the target that also adjusts the include path.
sync_source_lists_from_cmake now also looks for source files in
`sources += [ "foo.cc" ]` lines, which allows us to remove most
`# Make `gn format` not collapse this` comments.
(sync_source_lists_from_cmake doesn't look for `foo_headers += [...]`
still, so the comment is still needed in two places for that.)
No intentional behavior change.
Instead of detecting it automatically but also allowing for the setting
to be specified explicitly, always detect whether exceptions are enabled
based on whether -fno-rtti (or equivalent) is used. It's less confusing
to have a single way of tweaking that knob.
This change follows the lead of 71d88cebfb.
Instead of detecting it automatically (in libc++) and relying on
_LIBCXXABI_NO_EXCEPTIONS being set explicitly (in libc++abi), always
detect whether exceptions are enabled automatically.
This commit also removes support for specifying -D_LIBCPP_NO_EXCEPTIONS
and -D_LIBCXXABI_NO_EXCEPTIONS explicitly -- those should just be inferred
from using -fno-exceptions (or an equivalent flag).
Allowing both -D_FOO_NO_EXCEPTIONS to be provided explicitly and trying
to detect it automatically is just confusing, especially since we did
specify it explicitly when building libc++abi. We should have only one
way to detect whether exceptions are enabled, but it should be robust.
LLVM GN Syncbot