[libc++] Include <__config_site> from <__config>
Prior to this patch, we would generate a fancy <__config> header by
concatenating <__config_site> and <__config>. This complexifies the
build system and also increases the difference between what's tested
and what's actually installed.
This patch removes that complexity and instead simply installs <__config_site>
alongside the libc++ headers. <__config_site> is then included by <__config>,
which is much simpler. Doing this also opens the door to having different
<__config_site> headers depending on the target, which was impossible before.
It does change the workflow for testing header-only changes to libc++.
Previously, we would run `lit` against the headers in libcxx/include.
After this patch, we run it against a fake installation root of the
headers (containing a proper <__config_site> header). This makes use
closer to testing what we actually install, which is good, however it
does mean that we have to update that root before testing header changes.
Thus, we now need to run `ninja check-cxx-deps` before running `lit` by
hand.
Differential Revision: https://reviews.llvm.org/D89041
GitOrigin-RevId: 1e46d1aa3f9b618e8db32af5c855fbc386a950aa
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 015a359..bdfecf6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,6 +31,7 @@
set(LIBCXX_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
set(LIBCXX_BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR})
set(LIBCXX_BINARY_INCLUDE_DIR "${LIBCXX_BINARY_DIR}/include/c++build")
+set(LIBCXX_GENERATED_INCLUDE_DIR "${LIBCXX_BINARY_DIR}/include/c++/v1")
if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR OR LIBCXX_STANDALONE_BUILD)
project(libcxx CXX C)
diff --git a/docs/TestingLibcxx.rst b/docs/TestingLibcxx.rst
index d42becf..ec017e2 100644
--- a/docs/TestingLibcxx.rst
+++ b/docs/TestingLibcxx.rst
@@ -26,8 +26,8 @@
After building libc++, you can run parts of the libc++ test suite by simply
running ``llvm-lit`` on a specified test or directory. If you're unsure
-whether the required libraries have been built, you can use the
-`check-cxx-deps` target. For example:
+whether the required targets have been built, you can use the `check-cxx-deps`
+target to build them. For example:
.. code-block:: bash
@@ -37,6 +37,12 @@
$ <build>/bin/llvm-lit -sv libcxx/test/std/depr/depr.c.headers/stdlib_h.pass.cpp # Run a single test
$ <build>/bin/llvm-lit -sv libcxx/test/std/atomics libcxx/test/std/threads # Test std::thread and std::atomic
+In the default configuration, the tests are built against headers that form a
+fake installation root of libc++. This installation root has to be updated when
+changes are made to the headers, so you should re-run the `check-cxx-deps` target
+before running the tests manually with `lit` when you make any sort of change,
+including to the headers.
+
Sometimes you'll want to change the way LIT is running the tests. Custom options
can be specified using the `--param=<name>=<val>` flag. The most common option
you'll want to change is the standard dialect (ie -std=c++XX). By default the
diff --git a/include/CMakeLists.txt b/include/CMakeLists.txt
index 7c97db4..a8d6f74 100644
--- a/include/CMakeLists.txt
+++ b/include/CMakeLists.txt
@@ -2,6 +2,7 @@
__bit_reference
__bsd_locale_defaults.h
__bsd_locale_fallbacks.h
+ __config
__errc
__debug
__functional_03
@@ -184,62 +185,28 @@
)
endif()
-configure_file("__config_site.in"
- "${LIBCXX_BINARY_DIR}/__config_site"
- @ONLY)
-
-# Generate a custom __config header. The new header is created
-# by prepending __config_site to the current __config header.
-add_custom_command(OUTPUT ${LIBCXX_BINARY_DIR}/__generated_config
- COMMAND ${Python3_EXECUTABLE} ${LIBCXX_SOURCE_DIR}/utils/cat_files.py
- ${LIBCXX_BINARY_DIR}/__config_site
- ${LIBCXX_SOURCE_DIR}/include/__config
- -o ${LIBCXX_BINARY_DIR}/__generated_config
- DEPENDS ${LIBCXX_SOURCE_DIR}/include/__config
- ${LIBCXX_BINARY_DIR}/__config_site
-)
-# Add a target that executes the generation commands.
-add_custom_target(cxx-generated-config ALL
- DEPENDS ${LIBCXX_BINARY_DIR}/__generated_config)
-
if(LIBCXX_HEADER_DIR)
- set(output_dir ${LIBCXX_HEADER_DIR}/include/c++/v1)
+ configure_file("__config_site.in" "${LIBCXX_GENERATED_INCLUDE_DIR}/__config_site" @ONLY)
- set(out_files)
+ set(_all_includes "${LIBCXX_GENERATED_INCLUDE_DIR}/__config_site")
foreach(f ${files})
- set(src ${CMAKE_CURRENT_SOURCE_DIR}/${f})
- set(dst ${output_dir}/${f})
+ set(src "${CMAKE_CURRENT_SOURCE_DIR}/${f}")
+ set(dst "${LIBCXX_GENERATED_INCLUDE_DIR}/${f}")
add_custom_command(OUTPUT ${dst}
DEPENDS ${src}
COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src} ${dst}
COMMENT "Copying CXX header ${f}")
- list(APPEND out_files ${dst})
+ list(APPEND _all_includes "${dst}")
endforeach()
-
- # Copy the generated header as __config into build directory.
- set(src ${LIBCXX_BINARY_DIR}/__generated_config)
- set(dst ${output_dir}/__config)
- add_custom_command(OUTPUT ${dst}
- DEPENDS ${src} cxx-generated-config
- COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src} ${dst}
- COMMENT "Copying CXX __config")
- list(APPEND out_files ${dst})
- add_custom_target(generate-cxx-headers DEPENDS ${out_files})
+ add_custom_target(generate-cxx-headers DEPENDS ${_all_includes})
add_library(cxx-headers INTERFACE)
add_dependencies(cxx-headers generate-cxx-headers ${LIBCXX_CXX_ABI_HEADER_TARGET})
# TODO: Use target_include_directories once we figure out why that breaks the runtimes build
if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC" OR "${CMAKE_CXX_SIMULATE_ID}" STREQUAL "MSVC")
- target_compile_options(cxx-headers INTERFACE /I "${output_dir}")
+ target_compile_options(cxx-headers INTERFACE /I "${LIBCXX_GENERATED_INCLUDE_DIR}")
else()
- target_compile_options(cxx-headers INTERFACE -I "${output_dir}")
- endif()
-
- # Make sure the generated __config_site header is included when we build the library.
- if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC" OR "${CMAKE_CXX_SIMULATE_ID}" STREQUAL "MSVC")
- target_compile_options(cxx-headers INTERFACE /FI "${LIBCXX_BINARY_DIR}/__config_site")
- else()
- target_compile_options(cxx-headers INTERFACE -include "${LIBCXX_BINARY_DIR}/__config_site")
+ target_compile_options(cxx-headers INTERFACE -I "${LIBCXX_GENERATED_INCLUDE_DIR}")
endif()
else()
add_library(cxx-headers INTERFACE)
@@ -255,11 +222,10 @@
)
endforeach()
- # Install the generated header as __config.
- install(FILES ${LIBCXX_BINARY_DIR}/__generated_config
+ # Install the generated __config_site.
+ install(FILES ${LIBCXX_BINARY_DIR}/__config_site
DESTINATION ${LIBCXX_INSTALL_HEADER_PREFIX}include/c++/v1
PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
- RENAME __config
COMPONENT cxx-headers)
if (NOT CMAKE_CONFIGURATION_TYPES)
diff --git a/include/__config b/include/__config
index 8d2ab2e..d99e972 100644
--- a/include/__config
+++ b/include/__config
@@ -10,6 +10,8 @@
#ifndef _LIBCPP_CONFIG
#define _LIBCPP_CONFIG
+#include <__config_site>
+
#if defined(_MSC_VER) && !defined(__clang__)
# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# define _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
diff --git a/test/configs/legacy.cfg.in b/test/configs/legacy.cfg.in
index f0a4e8a..148ac3f 100644
--- a/test/configs/legacy.cfg.in
+++ b/test/configs/legacy.cfg.in
@@ -3,6 +3,7 @@
import os
import site
+config.cxx_headers = "@LIBCXX_GENERATED_INCLUDE_DIR@"
config.cxx_under_test = "@CMAKE_CXX_COMPILER@"
config.project_obj_root = "@CMAKE_BINARY_DIR@"
config.libcxx_src_root = "@LIBCXX_SOURCE_DIR@"
diff --git a/utils/libcxx/test/config.py b/utils/libcxx/test/config.py
index 0d21aa1..c5050d1 100644
--- a/utils/libcxx/test/config.py
+++ b/utils/libcxx/test/config.py
@@ -331,7 +331,6 @@
def configure_compile_flags_header_includes(self):
support_path = os.path.join(self.libcxx_src_root, 'test', 'support')
- self.configure_config_site_header()
if self.cxx_stdlib_under_test != 'libstdc++' and \
not self.target_info.is_windows():
self.cxx.compile_flags += [
@@ -348,16 +347,12 @@
'set_windows_crt_report_mode.h')
]
cxx_headers = self.get_lit_conf('cxx_headers')
- if cxx_headers == '' or (cxx_headers is None
- and self.cxx_stdlib_under_test != 'libc++'):
+ if cxx_headers is None and self.cxx_stdlib_under_test != 'libc++':
self.lit_config.note('using the system cxx headers')
return
self.cxx.compile_flags += ['-nostdinc++']
- if cxx_headers is None:
- cxx_headers = os.path.join(self.libcxx_src_root, 'include')
if not os.path.isdir(cxx_headers):
- self.lit_config.fatal("cxx_headers='%s' is not a directory."
- % cxx_headers)
+ self.lit_config.fatal("cxx_headers='{}' is not a directory.".format(cxx_headers))
self.cxx.compile_flags += ['-I' + cxx_headers]
if self.libcxx_obj_root is not None:
cxxabi_headers = os.path.join(self.libcxx_obj_root, 'include',
@@ -365,16 +360,6 @@
if os.path.isdir(cxxabi_headers):
self.cxx.compile_flags += ['-I' + cxxabi_headers]
- def configure_config_site_header(self):
- # Check for a possible __config_site in the build directory. We
- # use this if it exists.
- if self.libcxx_obj_root is None:
- return
- config_site_header = os.path.join(self.libcxx_obj_root, '__config_site')
- if not os.path.isfile(config_site_header):
- return
- self.cxx.compile_flags += ['-include', config_site_header]
-
def configure_link_flags(self):
# Configure library path
self.configure_link_flags_cxx_library_path()
