[libc++] Remove libc++ ARM builders

[ldionne]

Summary

In accordance with the announcement on libcxx-dev and llvm-dev [1],
we are removing the libc++ specific buildbots in favor of running
those configurations in the pre-commit CI on Buildkite. This commit
removes the ARM-based libc++ build bots.

[1]: http://lists.llvm.org/pipermail/libcxx-dev/2020-November/001040.html

[ldionne]

Note that this patch isn't ready to be merged yet. I'm only setting things up so that it's easy to remove the builders once those have been moved to Buildkite. I'm also unsure what's the Phabricator handle of the folks responsible for these bots.

[ldionne]

I think this is pretty much good to go now, since the Linaro bots are on BuildKite.

[DavidSpickett]

https://reviews.llvm.org/D98019 moves the v7/v8 bots, AArch64 is already done. LGTM once that's landed.

buildbot/osuosl/master/config/builders.py

# Libc++ builders.
     {'name' : 'libcxx-libcxxabi-singlethreaded-x86_64-linux-debian',
     'tags'  : ["libcxx"],
     'workernames' : ['gribozavr4'],
     'builddir': 'libcxx-libcxxabi-singlethreaded-x86_64-linux-debian',
     'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
                     env={'CC': 'clang', 'CXX': 'clang++'},
                     use_cache='Generic-singlethreaded.cmake')},
 
-    # ARMv7 LibC++ and LibC++abi tests (require Clang+RT)
-    {'name' : 'libcxx-libcxxabi-libunwind-armv7-linux',
-    'tags'  : ["libcxx"],
-    'workernames': ['linaro-tk1-02'],
-    'builddir': 'libcxx-libcxxabi-libunwind-armv7-linux',
-    'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
-                    cmake_extra_opts={
-                        'LIBCXXABI_USE_LLVM_UNWINDER': 'ON',
-                        'CMAKE_C_FLAGS': '-mcpu=cortex-a15 -marm',
-                        'CMAKE_CXX_FLAGS': '-mcpu=cortex-a15 -marm',
-                        'LLVM_PARALLEL_LINK_JOBS': '2'})},
-
-    # ARMv8 LibC++ and LibC++abi tests (require Clang+RT)
-    {'name' : 'libcxx-libcxxabi-libunwind-armv8-linux',
-    'tags'  : ["libcxx"],
-    'workernames' : ['linaro-armv8-libcxx'],
-    'builddir': 'libcxx-libcxxabi-libunwind-armv8-linux',
-    'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
-                    cmake_extra_opts={
-                        'LIBCXXABI_USE_LLVM_UNWINDER': 'ON',
-                        'CMAKE_C_FLAGS': '-mcpu=cortex-a57 -marm',
-                        'CMAKE_CXX_FLAGS': '-mcpu=cortex-a57 -marm'})},
-
-    # ARMv7 LibC++ and LibC++abi tests w/o EH (require Clang+RT)
-    {'name' : 'libcxx-libcxxabi-libunwind-armv7-linux-noexceptions',
-    'tags'  : ["libcxx"],
-    'workernames' : ['linaro-tk1-02'],
-    'builddir': 'libcxx-libcxxabi-libunwind-armv7-linux-noexceptions',
-    'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
-                    cmake_extra_opts={
-                        'LIBCXXABI_USE_LLVM_UNWINDER': 'ON',
-                        'LIBCXX_ENABLE_EXCEPTIONS': 'OFF',
-                        'LIBCXXABI_ENABLE_EXCEPTIONS': 'OFF',
-                        'CMAKE_C_FLAGS': '-mcpu=cortex-a15 -mthumb',
-                        'CMAKE_CXX_FLAGS': '-mcpu=cortex-a15 -mthumb',
-                        'LLVM_PARALLEL_LINK_JOBS': '2'})},
-
-    # ARMv8 LibC++ and LibC++abi tests w/o EH (require Clang+RT)
-    {'name' : 'libcxx-libcxxabi-libunwind-armv8-linux-noexceptions',
-    'tags'  : ["libcxx"],
-    'workernames' : ['linaro-armv8-libcxx'],
-    'builddir': 'libcxx-libcxxabi-libunwind-armv8-linux-noexceptions',
-    'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
-                    cmake_extra_opts={
-                        'LIBCXXABI_USE_LLVM_UNWINDER': 'ON',
-                        'LIBCXX_ENABLE_EXCEPTIONS': 'OFF',
-                        'LIBCXXABI_ENABLE_EXCEPTIONS': 'OFF',
-                        'CMAKE_C_FLAGS': '-mcpu=cortex-a57 -mthumb',
-                        'CMAKE_CXX_FLAGS': '-mcpu=cortex-a57 -mthumb'})},
-
-    # AArch64 LibC++ and LibC++abi tests (require Clang+RT)
-    {'name' : 'libcxx-libcxxabi-libunwind-aarch64-linux',
-    'tags'  : ["libcxx"],
-    'workernames' : ['linaro-aarch64-libcxx'],
-    'builddir': 'libcxx-libcxxabi-libunwind-aarch64-linux',
-    'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
-                    cmake_extra_opts={
-                        'LIBCXXABI_USE_LLVM_UNWINDER': 'ON',
-                        'CMAKE_C_FLAGS': '-mcpu=cortex-a57',
-                        'CMAKE_CXX_FLAGS': '-mcpu=cortex-a57'})},
-
-    {'name' : 'libcxx-libcxxabi-libunwind-aarch64-linux-noexceptions',
-    'tags'  : ["libcxx"],
-    'workernames' : ['linaro-aarch64-libcxx'],
-    'builddir': 'libcxx-libcxxabi-libunwind-aarch64-linux-noexceptions',
-    'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
-                    cmake_extra_opts={
-                        'LIBCXXABI_USE_LLVM_UNWINDER': 'ON',
-                        'LIBCXX_ENABLE_EXCEPTIONS': 'OFF',
-                        'LIBCXXABI_ENABLE_EXCEPTIONS': 'OFF',
-                        'CMAKE_C_FLAGS': '-mcpu=cortex-a57',
-                        'CMAKE_CXX_FLAGS': '-mcpu=cortex-a57'})},
-
     {'name' : 'libcxx-libcxxabi-libunwind-ppc-aix',
     'tags'  : ["libcxx"],
     'workernames' : ['aix-ppc-libcxx'],
     'builddir': 'libcxx-libcxxabi-libunwind-ppc-aix',
     'factory' : LibcxxAndAbiBuilder.getLibcxxAndAbiBuilder(
                     env={'OBJECT_MODE': '32'},
                     cmake_extra_opts={
                         'CMAKE_BUILD_TYPE': 'Release',