[libcxx] Allow tests to link with static libc++abi/libc++ even if the shared version is present

[broadwaylamb]

Summary

This is essentially D71894, but for libc++.

This is needed for running libc++ tests over SSH.

[broadwaylamb]

Fix a typo

[phosek]

libcxx/CMakeLists.txt

80 ↗

(On Diff #237892)

Have you considered using cmake_dependent_option? That way you don't need to do the validation below yourself.

[broadwaylamb]

I'm going to update this to be consistent with D71894.

[broadwaylamb]

Update to match D71894.

Tested with:

• native macOS toolchain, linking against the system libc++abi and just-built libc++.
• cross-toolchain (Windows -> ARM Linux), linking against the just-built libc++abi and libc++.

[phosek]

LGTM

[broadwaylamb]

@ldionne can I get your LGTM as well?

[ldionne]

FWIW, I'm working on a refactoring of the way we configure lit that should get rid of pretty much all testing logic inside libc++ and libc++abi's CMake files. So I'm OK with this change if it helps you right now, however if what I'm working on works well, we'll get rid of it.

[broadwaylamb]

@ldionne sure.

[ldionne]

This broke CMake configuration with the following set of arguments: -DLLVM_ENABLE_PROJECTS=libcxx -DLIBCXX_ENABLE_SHARED=OFF -DLIBCXX_ENABLE_STATIC=OFF -DLIBCXX_INCLUDE_TESTS=OFF. Fixed in:

commit b58902bc72c2b479b5ed27ec0d3422ba9782edbb
Author: Louis Dionne <[e-mail]>
Date:   Wed Mar 25 16:50:19 2020 -0400

    [libc++] Fix CMake configuration breakage when libc++ is built neither static nor dynamic

    Introduced by https://reviews.llvm.org/D72687. This condition can happen
    when the tests are not being run at all, and we're only trying to generate
    the libc++ headers.

libcxx/test/CMakeLists.txt

 endif()
 
 # The tests shouldn't link to libunwind if we have a linker script which
 # already does so.
 if (LIBCXX_ENABLE_ABI_LINKER_SCRIPT)
   set(LIBCXXABI_USE_LLVM_UNWINDER OFF)
 endif()
 
+option(LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI
+       "Whether the libc++ tests should link with the shared libc++abi library"
+       ${LIBCXXABI_ENABLE_SHARED})
+
+option(LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXX
+       "Whether the libc++ tests should link with the shared libc++ library"
+       ${LIBCXX_ENABLE_SHARED})
+
+if(DEFINED LIBCXXABI_ENABLE_SHARED
+   AND LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI
+   AND NOT LIBCXXABI_ENABLE_SHARED)
+  message(FATAL_ERROR "LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI being ON requires LIBCXXABI_ENABLE_SHARED to be ON")
+endif()
+
+if(DEFINED LIBCXXABI_ENABLE_STATIC
+   AND NOT LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI
+   AND NOT LIBCXXABI_ENABLE_STATIC)
+  message(FATAL_ERROR "LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI being OFF requires LIBCXXABI_ENABLE_STATIC to be ON")
+endif()
+
+if(LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXX AND NOT LIBCXX_ENABLE_SHARED)
+  message(FATAL_ERROR "LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXX being ON requires LIBCXX_ENABLE_SHARED to be ON")
+endif()
+
+if(NOT LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXX AND NOT LIBCXX_ENABLE_STATIC)
+  message(FATAL_ERROR "LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXX being OFF requires LIBCXX_ENABLE_STATIC to be ON")
+endif()
+
 pythonize_bool(LIBCXX_ENABLE_EXCEPTIONS)
 pythonize_bool(LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY)
 pythonize_bool(LIBCXX_ENABLE_RTTI)
 pythonize_bool(LIBCXX_ENABLE_SHARED)
+pythonize_bool(LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXX)
+pythonize_bool(LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI)
 pythonize_bool(LIBCXX_ENABLE_FILESYSTEM)
 pythonize_bool(LIBCXX_BUILD_32_BITS)
 pythonize_bool(LIBCXX_GENERATE_COVERAGE)
 pythonize_bool(LIBCXXABI_ENABLE_SHARED)
 pythonize_bool(LIBCXXABI_USE_LLVM_UNWINDER)
 pythonize_bool(LIBCXX_USE_COMPILER_RT)
 pythonize_bool(LIBCXX_HAS_ATOMIC_LIB)
 pythonize_bool(LIBCXX_HAVE_CXX_ATOMICS_WITH_LIB)

libcxx/test/lit.site.cfg.in

 @AUTO_GEN_COMMENT@
 config.cxx_under_test           = "@LIBCXX_COMPILER@"
 config.project_obj_root         = "@CMAKE_BINARY_DIR@"
 config.libcxx_src_root          = "@LIBCXX_SOURCE_DIR@"
 config.libcxx_obj_root          = "@LIBCXX_BINARY_DIR@"
 config.cxx_library_root         = "@LIBCXX_LIBRARY_DIR@"
 config.enable_exceptions        = @LIBCXX_ENABLE_EXCEPTIONS@
 config.enable_experimental      = @LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY@
 config.enable_filesystem        = @LIBCXX_ENABLE_FILESYSTEM@
 config.enable_rtti              = @LIBCXX_ENABLE_RTTI@
-config.enable_shared            = @LIBCXX_ENABLE_SHARED@
+config.enable_shared            = @LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXX@
 config.enable_32bit             = @LIBCXX_BUILD_32_BITS@
 config.cxx_abi                  = "@LIBCXX_CXX_ABI_LIBNAME@"
 config.use_sanitizer            = "@LLVM_USE_SANITIZER@"
 config.sanitizer_library        = "@LIBCXX_SANITIZER_LIBRARY@"
 config.abi_library_path         = "@LIBCXX_CXX_ABI_LIBRARY_PATH@"
 config.configuration_variant    = "@LIBCXX_LIT_VARIANT@"
 config.host_triple              = "@LLVM_HOST_TRIPLE@"
 config.target_triple            = "@TARGET_TRIPLE@"
 config.use_target               = bool("@LIBCXX_TARGET_TRIPLE@")
 config.sysroot                  = "@LIBCXX_SYSROOT@"
 config.gcc_toolchain            = "@LIBCXX_GCC_TOOLCHAIN@"
 config.generate_coverage        = @LIBCXX_GENERATE_COVERAGE@
 config.target_info              = "@LIBCXX_TARGET_INFO@"
 config.test_linker_flags        = "@LIBCXX_TEST_LINKER_FLAGS@"
 config.test_compiler_flags      = "@LIBCXX_TEST_COMPILER_FLAGS@"
 
 config.executor                 = "@LIBCXX_EXECUTOR@"
 config.llvm_unwinder            = @LIBCXXABI_USE_LLVM_UNWINDER@
 config.builtins_library         = "@LIBCXX_BUILTINS_LIBRARY@"
 config.has_libatomic            = @LIBCXX_HAS_ATOMIC_LIB@
 config.use_libatomic            = @LIBCXX_HAVE_CXX_ATOMICS_WITH_LIB@
 config.debug_build              = @LIBCXX_DEBUG_BUILD@
-config.libcxxabi_shared         = @LIBCXXABI_ENABLE_SHARED@
+config.libcxxabi_shared         = @LIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI@
 config.cxx_ext_threads          = @LIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY@
 config.pstl_src_root            = "@ParallelSTL_SOURCE_DIR@" if @LIBCXX_ENABLE_PARALLEL_ALGORITHMS@ else None
 config.pstl_obj_root            = "@ParallelSTL_BINARY_DIR@" if @LIBCXX_ENABLE_PARALLEL_ALGORITHMS@ else None
 config.libcxx_gdb               = "@LIBCXX_GDB@"
 
 # Code signing
 config.llvm_codesign_identity   = "@LLVM_CODESIGNING_IDENTITY@"
 
 # Let the main config do the real work.
 config.loaded_site_config = True
 lit_config.load_config(config, "@LIBCXX_SOURCE_DIR@/test/lit.cfg")