[libcxx-commits] [libcxxabi] 529ac33 - [libc++abi] Fix the standalone build after the __config_site change

[Louis Dionne via libcxx-commits]

Author: Louis Dionne
Date: 2020-10-22T19:17:20-04:00
New Revision: 529ac33197f6408952ae995075ac5e2dc5287e81

URL: https://github.com/llvm/llvm-project/commit/529ac33197f6408952ae995075ac5e2dc5287e81
DIFF: https://github.com/llvm/llvm-project/commit/529ac33197f6408952ae995075ac5e2dc5287e81.diff

LOG: [libc++abi] Fix the standalone build after the __config_site change

In 5d796645, we stopped looking at the LIBCXXABI_LIBCXX_INCLUDES variable,
which broke users of the Standalone build. This patch reinstates that
variable, however it must point to the *installed* path of the libc++
headers, not the libc++ headers in the source tree (which has always
been the case, but wasn't enforced before).

If LIBCXXABI_LIBCXX_INCLUDES points to the libc++ headers in the source
tree, the `__config_site` header will fail to be found.

Added: 
    

Modified: 
    libcxxabi/CMakeLists.txt
    libcxxabi/test/libcxxabi/test/config.py
    libcxxabi/test/lit.site.cfg.in

Removed: 
    


################################################################################
diff  --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
index f0593bc2a076..a5d3a06a20a6 100644
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -138,6 +138,24 @@ if (NOT LIBCXXABI_ENABLE_SHARED AND NOT LIBCXXABI_ENABLE_STATIC)
   message(FATAL_ERROR "libc++abi must be built as either a shared or static library.")
 endif()
 
+# TODO: This is a hack for the fact that Standalone builds can't use targets
+#       from the other runtimes (so the cxx-headers target doesn't exist).
+set(LIBCXXABI_LIBCXX_INCLUDES "" CACHE PATH
+    "Specify path to the installed libc++ includes. This is only relevant for Standalone builds, where the location of the headers can't be determined automatically.")
+if (LIBCXXABI_STANDALONE_BUILD)
+  if (NOT IS_DIRECTORY ${LIBCXXABI_LIBCXX_INCLUDES})
+    message(FATAL_ERROR
+      "LIBCXXABI_LIBCXX_INCLUDES=${LIBCXXABI_LIBCXX_INCLUDES} is not a valid directory. "
+      "Please provide the path to where the libc++ headers have been installed.")
+  endif()
+  add_library(cxx-headers INTERFACE)
+  if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC" OR "${CMAKE_CXX_SIMULATE_ID}" STREQUAL "MSVC")
+    target_compile_options(cxx-headers INTERFACE /I "${LIBCXXABI_LIBCXX_INCLUDES}")
+  else()
+    target_compile_options(cxx-headers INTERFACE -I "${LIBCXXABI_LIBCXX_INCLUDES}")
+  endif()
+endif()
+
 option(LIBCXXABI_HERMETIC_STATIC_LIBRARY
   "Do not export any symbols from the static library." OFF)
 

diff  --git a/libcxxabi/test/libcxxabi/test/config.py b/libcxxabi/test/libcxxabi/test/config.py
index e7c019688f1a..f9e17e9f97da 100644
--- a/libcxxabi/test/libcxxabi/test/config.py
+++ b/libcxxabi/test/libcxxabi/test/config.py
@@ -56,9 +56,8 @@ def configure_compile_flags(self):
         super(Configuration, self).configure_compile_flags()
 
     def configure_compile_flags_header_includes(self):
-        cxx_headers = self.get_lit_conf(
-            'cxx_headers',
-            os.path.join(self.project_obj_root, 'include', 'c++', 'v1'))
+        cxx_headers = self.get_lit_conf('cxx_headers', None) or \
+                    os.path.join(self.project_obj_root, 'include', 'c++', 'v1')
         if cxx_headers == '':
             self.lit_config.note('using the systems c++ headers')
         else:

diff  --git a/libcxxabi/test/lit.site.cfg.in b/libcxxabi/test/lit.site.cfg.in
index a6d43c6e2da1..87f955e32161 100644
--- a/libcxxabi/test/lit.site.cfg.in
+++ b/libcxxabi/test/lit.site.cfg.in
@@ -9,6 +9,7 @@ config.libcxxabi_src_root       = "@LIBCXXABI_SOURCE_DIR@"
 config.libcxxabi_obj_root       = "@LIBCXXABI_BINARY_DIR@"
 config.abi_library_path         = "@LIBCXXABI_LIBRARY_DIR@"
 config.libcxx_src_root          = "@LIBCXXABI_LIBCXX_PATH@"
+config.cxx_headers              = "@LIBCXXABI_LIBCXX_INCLUDES@"
 config.libunwind_headers        = "@LIBCXXABI_LIBUNWIND_INCLUDES_INTERNAL@"
 config.cxx_library_root         = "@LIBCXXABI_LIBCXX_LIBRARY_PATH@"
 config.llvm_unwinder            = @LIBCXXABI_USE_LLVM_UNWINDER@