forked from OSchip/llvm-project
[libcxx] Capture configuration information when installing the libc++ headers
Summary: Hi all, This patch is a successor to D11963. However it has changed dramatically and I felt it would be best to start a new review thread. Please read the design documentation added in this patch for a description of how it works. Reviewers: mclow.lists, danalbert, jroelofs, EricWF Subscribers: vkalintiris, rnk, ed, espositofulvio, asl, eugenis, cfe-commits Differential Revision: http://reviews.llvm.org/D13407 llvm-svn: 250235
This commit is contained in:
Eric Fiselier
parent
eba62796cb
commit
f9f796e79b
|
|
@ -260,13 +260,6 @@ endif()
|
|||
|
||||
# Feature flags ===============================================================
|
||||
define_if(MSVC -D_CRT_SECURE_NO_WARNINGS)
|
||||
define_if_not(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE -D_LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE)
|
||||
define_if_not(LIBCXX_ENABLE_STDIN -D_LIBCPP_HAS_NO_STDIN)
|
||||
define_if_not(LIBCXX_ENABLE_STDOUT -D_LIBCPP_HAS_NO_STDOUT)
|
||||
define_if_not(LIBCXX_ENABLE_THREADS -D_LIBCPP_HAS_NO_THREADS)
|
||||
define_if_not(LIBCXX_ENABLE_MONOTONIC_CLOCK -D_LIBCPP_HAS_NO_MONOTONIC_CLOCK)
|
||||
define_if_not(LIBCXX_ENABLE_THREAD_UNSAFE_C_FUNCTIONS -D_LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS)
|
||||
|
||||
|
||||
# Sanitizer flags =============================================================
|
||||
|
||||
|
|
@ -303,6 +296,22 @@ if (LIBCXX_BUILT_STANDALONE)
|
|||
message(WARNING "LLVM_USE_SANITIZER is not supported on this platform.")
|
||||
endif()
|
||||
endif()
|
||||
|
||||
# Configuration file flags =====================================================
|
||||
config_define_if_not(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE)
|
||||
config_define_if_not(LIBCXX_ENABLE_STDIN _LIBCPP_HAS_NO_STDIN)
|
||||
config_define_if_not(LIBCXX_ENABLE_STDOUT _LIBCPP_HAS_NO_STDOUT)
|
||||
config_define_if_not(LIBCXX_ENABLE_THREADS _LIBCPP_HAS_NO_THREADS)
|
||||
config_define_if_not(LIBCXX_ENABLE_MONOTONIC_CLOCK _LIBCPP_HAS_NO_MONOTONIC_CLOCK)
|
||||
config_define_if_not(LIBCXX_ENABLE_THREAD_UNSAFE_C_FUNCTIONS _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS)
|
||||
|
||||
if (LIBCXX_NEEDS_SITE_CONFIG)
|
||||
configure_file(
|
||||
include/__config_site.in
|
||||
${LIBCXX_BINARY_DIR}/__config_site
|
||||
@ONLY)
|
||||
endif()
|
||||
|
||||
#===============================================================================
|
||||
# Setup Source Code And Tests
|
||||
#===============================================================================
|
||||
|
|
|
|||
|
|
@ -49,6 +49,22 @@ macro(define_if_not condition def)
|
|||
endif()
|
||||
endmacro()
|
||||
|
||||
macro(config_define_if condition def)
|
||||
if (${condition})
|
||||
set(${def} ON)
|
||||
add_definitions(-D${def})
|
||||
set(LIBCXX_NEEDS_SITE_CONFIG ON)
|
||||
endif()
|
||||
endmacro()
|
||||
|
||||
macro(config_define_if_not condition def)
|
||||
if (NOT ${condition})
|
||||
set(${def} ON)
|
||||
add_definitions(-D${def})
|
||||
set(LIBCXX_NEEDS_SITE_CONFIG ON)
|
||||
endif()
|
||||
endmacro()
|
||||
|
||||
# Add a specified list of flags to both 'LIBCXX_COMPILE_FLAGS' and
|
||||
# 'LIBCXX_LINK_FLAGS'.
|
||||
macro(add_flags)
|
||||
|
|
|
|||
|
|
@ -0,0 +1,88 @@
|
|||
=======================================================
|
||||
Capturing configuration information during installation
|
||||
=======================================================
|
||||
|
||||
.. contents::
|
||||
:local:
|
||||
|
||||
The Problem
|
||||
===========
|
||||
|
||||
Currently the libc++ supports building the library with a number of different
|
||||
configuration options. Unfortunately all of that configuration information is
|
||||
lost when libc++ is installed. In order to support "persistent"
|
||||
configurations libc++ needs a mechanism to capture the configuration options
|
||||
in the INSTALLED headers.
|
||||
|
||||
|
||||
Design Goals
|
||||
============
|
||||
|
||||
* The solution should not INSTALL any additional headers. We don't want an extra
|
||||
#include slowing everybody down.
|
||||
|
||||
* The solution should not unduly affect libc++ developers. The problem is limited
|
||||
to installed versions of libc++ and the solution should be as well.
|
||||
|
||||
* The solution should not modify any existing headers EXCEPT during installation.
|
||||
It makes developers lives harder if they have to regenerate the libc++ headers
|
||||
every time they are modified.
|
||||
|
||||
* The solution should not make any of the libc++ headers dependant on
|
||||
files generated by the build system. The headers should be able to compile
|
||||
out of the box without any modification.
|
||||
|
||||
* The solution should not have ANY effect on users who don't need special
|
||||
configuration options. The vast majority of users will never need this so it
|
||||
shouldn't cost them.
|
||||
|
||||
|
||||
The Solution
|
||||
============
|
||||
|
||||
When you first configure libc++ using CMake we check to see if we need to
|
||||
capture any options. If we haven't been given any "persistent" options then
|
||||
we do NOTHING.
|
||||
|
||||
Otherwise we create a custom installation rule that modifies the installed __config
|
||||
header. The rule first generates a dummy "__config_site" header containing the required
|
||||
#defines. The contents of the dummy header are then prependend to the installed
|
||||
__config header. By manually prepending the files we avoid the cost of an
|
||||
extra #include and we allow the __config header to be ignorant of the extra
|
||||
configuration all together. An example "__config" header generated when
|
||||
-DLIBCXX_ENABLE_THREADS=OFF is given to CMake would look something like:
|
||||
|
||||
.. code-block:: cpp
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
//
|
||||
// The LLVM Compiler Infrastructure
|
||||
//
|
||||
// This file is dual licensed under the MIT and the University of Illinois Open
|
||||
// Source Licenses. See LICENSE.TXT for details.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
#ifndef _LIBCPP_CONFIG_SITE
|
||||
#define _LIBCPP_CONFIG_SITE
|
||||
|
||||
/* #undef _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE */
|
||||
/* #undef _LIBCPP_HAS_NO_STDIN */
|
||||
/* #undef _LIBCPP_HAS_NO_STDOUT */
|
||||
#define _LIBCPP_HAS_NO_THREADS
|
||||
/* #undef _LIBCPP_HAS_NO_MONOTONIC_CLOCK */
|
||||
/* #undef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS */
|
||||
|
||||
#endif
|
||||
// -*- C++ -*-
|
||||
//===--------------------------- __config ---------------------------------===//
|
||||
//
|
||||
// The LLVM Compiler Infrastructure
|
||||
//
|
||||
// This file is dual licensed under the MIT and the University of Illinois Open
|
||||
// Source Licenses. See LICENSE.TXT for details.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
#ifndef _LIBCPP_CONFIG
|
||||
#define _LIBCPP_CONFIG
|
||||
|
|
@ -124,6 +124,12 @@ A full list of currently open libc++ bugs can be `found here`__.
|
|||
Design Documents
|
||||
----------------
|
||||
|
||||
.. toctree::
|
||||
:maxdepth: 1
|
||||
|
||||
DesignDocs/CapturingConfigInfo
|
||||
|
||||
|
||||
* `<atomic> design <http://libcxx.llvm.org/atomic_design.html>`_
|
||||
* `<type_traits> design <http://libcxx.llvm.org/type_traits_design.html>`_
|
||||
* `Status of debug mode <http://libcxx.llvm.org/debug_mode.html>`_
|
||||
|
|
|
|||
|
|
@ -1,10 +1,12 @@
|
|||
if (NOT LIBCXX_INSTALL_SUPPORT_HEADERS)
|
||||
set(LIBCXX_SUPPORT_HEADER_PATTERN PATTERN "support" EXCLUDE)
|
||||
endif()
|
||||
|
||||
set(LIBCXX_HEADER_PATTERN
|
||||
PATTERN "*"
|
||||
PATTERN "CMakeLists.txt" EXCLUDE
|
||||
PATTERN ".svn" EXCLUDE
|
||||
PATTERN "__config_site.in" EXCLUDE
|
||||
${LIBCXX_SUPPORT_HEADER_PATTERN}
|
||||
)
|
||||
|
||||
|
|
@ -22,4 +24,29 @@ if (LIBCXX_INSTALL_HEADERS)
|
|||
${LIBCXX_HEADER_PATTERN}
|
||||
PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
|
||||
)
|
||||
|
||||
if (LIBCXX_NEEDS_SITE_CONFIG)
|
||||
set(UNIX_CAT cat)
|
||||
if (WIN32)
|
||||
set(UNIX_CAT type)
|
||||
endif()
|
||||
# Generate and install 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 ${CMAKE_COMMAND} -E copy ${LIBCXX_BINARY_DIR}/__config_site ${LIBCXX_BINARY_DIR}/__generated_config
|
||||
COMMAND ${UNIX_CAT} ${LIBCXX_SOURCE_DIR}/include/__config >> ${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(generate_config_header ALL
|
||||
DEPENDS ${LIBCXX_BINARY_DIR}/__generated_config)
|
||||
# Install the generated header as __config.
|
||||
install(FILES ${LIBCXX_BINARY_DIR}/__generated_config
|
||||
DESTINATION include/c++/v1
|
||||
PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
|
||||
RENAME __config
|
||||
COMPONENT libcxx)
|
||||
endif()
|
||||
|
||||
endif()
|
||||
|
|
|
|||
|
|
@ -0,0 +1,20 @@
|
|||
//===----------------------------------------------------------------------===//
|
||||
//
|
||||
// The LLVM Compiler Infrastructure
|
||||
//
|
||||
// This file is dual licensed under the MIT and the University of Illinois Open
|
||||
// Source Licenses. See LICENSE.TXT for details.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
#ifndef _LIBCPP_CONFIG_SITE
|
||||
#define _LIBCPP_CONFIG_SITE
|
||||
|
||||
#cmakedefine _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
|
||||
#cmakedefine _LIBCPP_HAS_NO_STDIN
|
||||
#cmakedefine _LIBCPP_HAS_NO_STDOUT
|
||||
#cmakedefine _LIBCPP_HAS_NO_THREADS
|
||||
#cmakedefine _LIBCPP_HAS_NO_MONOTONIC_CLOCK
|
||||
#cmakedefine _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
|
||||
|
||||
#endif
|
||||
Loading…
Reference in New Issue