[libcxx] r250254 - ABI versioning macros for libc++.
Evgeniy Stepanov via cfe-commits
cfe-commits at lists.llvm.org
Tue Oct 13 16:48:28 PDT 2015
Author: eugenis
Date: Tue Oct 13 18:48:28 2015
New Revision: 250254
URL: http://llvm.org/viewvc/llvm-project?rev=250254&view=rev
Log:
ABI versioning macros for libc++.
C++ macros and CMake options that specify the default ABI version of
the library, and can be overridden to pick up new ABI-changing
features.
Added:
libcxx/trunk/docs/Abi.rst
Modified:
libcxx/trunk/CMakeLists.txt
libcxx/trunk/cmake/Modules/HandleLibcxxFlags.cmake
libcxx/trunk/docs/BuildingLibcxx.rst
libcxx/trunk/include/__config
libcxx/trunk/include/__config_site.in
libcxx/trunk/include/string
libcxx/trunk/lib/CMakeLists.txt
libcxx/trunk/test/CMakeLists.txt
libcxx/trunk/test/libcxx/test/config.py
libcxx/trunk/test/lit.site.cfg.in
Modified: libcxx/trunk/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/CMakeLists.txt?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/CMakeLists.txt (original)
+++ libcxx/trunk/CMakeLists.txt Tue Oct 13 18:48:28 2015
@@ -58,6 +58,8 @@ set(LIBCXX_LIBDIR_SUFFIX "${LLVM_LIBDIR_
option(LIBCXX_INSTALL_HEADERS "Install the libc++ headers." ON)
option(LIBCXX_INSTALL_LIBRARY "Install the libc++ library." ON)
option(LIBCXX_INSTALL_SUPPORT_HEADERS "Install libc++ support headers." ON)
+set(LIBCXX_ABI_VERSION 1 CACHE STRING "ABI version of libc++.")
+option(LIBCXX_ABI_UNSTABLE "Unstable ABI of libc++." OFF)
# ABI Library options ---------------------------------------------------------
set(LIBCXX_CXX_ABI "${LIBCXX_CXX_ABI}" CACHE STRING
@@ -298,6 +300,11 @@ if (LIBCXX_BUILT_STANDALONE)
endif()
# Configuration file flags =====================================================
+if (NOT LIBCXX_ABI_VERSION EQUAL "1")
+ config_define(${LIBCXX_ABI_VERSION} _LIBCPP_ABI_VERSION)
+endif()
+config_define_if(LIBCXX_ABI_UNSTABLE _LIBCPP_ABI_UNSTABLE)
+
config_define_if_not(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE)
config_define_if_not(LIBCXX_ENABLE_STDIN _LIBCPP_HAS_NO_STDIN)
config_define_if_not(LIBCXX_ENABLE_STDOUT _LIBCPP_HAS_NO_STDOUT)
Modified: libcxx/trunk/cmake/Modules/HandleLibcxxFlags.cmake
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/cmake/Modules/HandleLibcxxFlags.cmake?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/cmake/Modules/HandleLibcxxFlags.cmake (original)
+++ libcxx/trunk/cmake/Modules/HandleLibcxxFlags.cmake Tue Oct 13 18:48:28 2015
@@ -65,6 +65,12 @@ macro(config_define_if_not condition def
endif()
endmacro()
+macro(config_define value def)
+ set(${def} ${value})
+ add_definitions(-D${def}=${value})
+ set(LIBCXX_NEEDS_SITE_CONFIG ON)
+endmacro()
+
# Add a specified list of flags to both 'LIBCXX_COMPILE_FLAGS' and
# 'LIBCXX_LINK_FLAGS'.
macro(add_flags)
Added: libcxx/trunk/docs/Abi.rst
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/docs/Abi.rst?rev=250254&view=auto
==============================================================================
--- libcxx/trunk/docs/Abi.rst (added)
+++ libcxx/trunk/docs/Abi.rst Tue Oct 13 18:48:28 2015
@@ -0,0 +1,17 @@
+
+====================
+Libc++ ABI stability
+====================
+
+Libc++ aims to preserve stable ABI to avoid subtle bugs when code built to the old ABI
+is linked with the code build to the new ABI. At the same time, libc++ allows ABI-breaking
+improvements and bugfixes for the scenarios when ABI change is not a issue.
+
+To support both cases, libc++ allows specifying the ABI version at the
+build time. The version is defined with a cmake option
+LIBCXX_ABI_VERSION. Another option LIBCXX_ABI_UNSTABLE can be used to
+include all present ABI breaking features. These options translate
+into C++ macro definitions _LIBCPP_ABI_VERSION, _LIBCPP_ABI_UNSTABLE.
+
+Any ABI-changing feature is placed under it's own macro, _LIBCPP_ABI_XXX, which is enabled
+based on the value of _LIBCPP_ABI_VERSION. _LIBCPP_ABI_UNSTABLE, if set, enables all features at once.
Modified: libcxx/trunk/docs/BuildingLibcxx.rst
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/docs/BuildingLibcxx.rst?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/docs/BuildingLibcxx.rst (original)
+++ libcxx/trunk/docs/BuildingLibcxx.rst Tue Oct 13 18:48:28 2015
@@ -193,6 +193,25 @@ libc++ Feature options
Build libc++ with run time type information.
+
+libc++ Feature options
+----------------------
+
+The following options allow building libc++ for a different ABI version.
+
+.. option:: LIBCXX_ABI_VERSION:STRING
+
+ **Default**: ``1``
+
+ Defines the target ABI version of libc++.
+
+.. option:: LIBCXX_ABI_UNSTABLE:BOOL
+
+ **Default**: ``OFF``
+
+ Build the "unstable" ABI version of libc++. Includes all ABI changing features
+ on top of the current stable version.
+
.. _LLVM-specific variables:
LLVM-specific options
Modified: libcxx/trunk/include/__config
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/__config?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/include/__config (original)
+++ libcxx/trunk/include/__config Tue Oct 13 18:48:28 2015
@@ -23,7 +23,13 @@
#define _LIBCPP_VERSION 3800
+#ifndef _LIBCPP_ABI_VERSION
#define _LIBCPP_ABI_VERSION 1
+#endif
+
+#if defined(_LIBCPP_ABI_UNSTABLE) || _LIBCPP_ABI_VERSION >= 2
+#define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+#endif
#define _LIBCPP_CONCAT1(_LIBCPP_X,_LIBCPP_Y) _LIBCPP_X##_LIBCPP_Y
#define _LIBCPP_CONCAT(_LIBCPP_X,_LIBCPP_Y) _LIBCPP_CONCAT1(_LIBCPP_X,_LIBCPP_Y)
@@ -240,9 +246,12 @@
#if defined(__clang__)
-#if defined(__APPLE__) && !defined(__i386__) && !defined(__x86_64__) && \
- !defined(__arm__)
-#define _LIBCPP_ALTERNATE_STRING_LAYOUT
+// _LIBCPP_ALTERNATE_STRING_LAYOUT is an old name for
+// _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT left here for backward compatibility.
+#if (defined(__APPLE__) && !defined(__i386__) && !defined(__x86_64__) && \
+ !defined(__arm__)) || \
+ defined(_LIBCPP_ALTERNATE_STRING_LAYOUT)
+#define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
#endif
#if __has_feature(cxx_alignas)
Modified: libcxx/trunk/include/__config_site.in
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/__config_site.in?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/include/__config_site.in (original)
+++ libcxx/trunk/include/__config_site.in Tue Oct 13 18:48:28 2015
@@ -10,6 +10,8 @@
#ifndef _LIBCPP_CONFIG_SITE
#define _LIBCPP_CONFIG_SITE
+#cmakedefine _LIBCPP_ABI_VERSION @_LIBCPP_ABI_VERSION@
+#cmakedefine _LIBCPP_ABI_UNSTABLE
#cmakedefine _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
#cmakedefine _LIBCPP_HAS_NO_STDIN
#cmakedefine _LIBCPP_HAS_NO_STDOUT
Modified: libcxx/trunk/include/string
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/string?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/include/string (original)
+++ libcxx/trunk/include/string Tue Oct 13 18:48:28 2015
@@ -1185,7 +1185,7 @@ _LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_TY
#pragma warning( pop )
#endif // _LIBCPP_MSVC
-#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
+#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
template <class _CharT, size_t = sizeof(_CharT)>
struct __padding
@@ -1198,7 +1198,7 @@ struct __padding<_CharT, 1>
{
};
-#endif // _LIBCPP_ALTERNATE_STRING_LAYOUT
+#endif // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
template<class _CharT, class _Traits, class _Allocator>
class _LIBCPP_TYPE_VIS_ONLY basic_string
@@ -1234,7 +1234,7 @@ public:
private:
-#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
+#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
struct __long
{
@@ -1294,7 +1294,7 @@ private:
value_type __data_[__min_cap];
};
-#endif // _LIBCPP_ALTERNATE_STRING_LAYOUT
+#endif // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
union __ulx{__long __lx; __short __lxx;};
@@ -1698,7 +1698,7 @@ private:
const allocator_type& __alloc() const _NOEXCEPT
{return __r_.second();}
-#ifdef _LIBCPP_ALTERNATE_STRING_LAYOUT
+#ifdef _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
_LIBCPP_INLINE_VISIBILITY
void __set_short_size(size_type __s) _NOEXCEPT
@@ -1716,7 +1716,7 @@ private:
{return __r_.first().__s.__size_;}
# endif
-#else // _LIBCPP_ALTERNATE_STRING_LAYOUT
+#else // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
_LIBCPP_INLINE_VISIBILITY
void __set_short_size(size_type __s) _NOEXCEPT
@@ -1734,7 +1734,7 @@ private:
{return __r_.first().__s.__size_ >> 1;}
# endif
-#endif // _LIBCPP_ALTERNATE_STRING_LAYOUT
+#endif // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
_LIBCPP_INLINE_VISIBILITY
void __set_long_size(size_type __s) _NOEXCEPT
Modified: libcxx/trunk/lib/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/lib/CMakeLists.txt?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/lib/CMakeLists.txt (original)
+++ libcxx/trunk/lib/CMakeLists.txt Tue Oct 13 18:48:28 2015
@@ -129,8 +129,8 @@ set_target_properties(cxx
COMPILE_FLAGS "${LIBCXX_COMPILE_FLAGS}"
LINK_FLAGS "${LIBCXX_LINK_FLAGS}"
OUTPUT_NAME "c++"
- VERSION "1.0"
- SOVERSION "1"
+ VERSION "${LIBCXX_ABI_VERSION}.0"
+ SOVERSION "${LIBCXX_ABI_VERSION}"
)
if (LIBCXX_INSTALL_LIBRARY)
Modified: libcxx/trunk/test/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/CMakeLists.txt?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/test/CMakeLists.txt (original)
+++ libcxx/trunk/test/CMakeLists.txt Tue Oct 13 18:48:28 2015
@@ -13,6 +13,7 @@ pythonize_bool(LIBCXX_ENABLE_EXCEPTIONS)
pythonize_bool(LIBCXX_ENABLE_RTTI)
pythonize_bool(LIBCXX_ENABLE_SHARED)
pythonize_bool(LIBCXX_BUILD_32_BITS)
+pythonize_bool(LIBCXX_ABI_UNSTABLE)
pythonize_bool(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE)
pythonize_bool(LIBCXX_ENABLE_STDIN)
pythonize_bool(LIBCXX_ENABLE_STDOUT)
Modified: libcxx/trunk/test/libcxx/test/config.py
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/test/config.py?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/test/libcxx/test/config.py (original)
+++ libcxx/trunk/test/libcxx/test/config.py Tue Oct 13 18:48:28 2015
@@ -387,6 +387,7 @@ class Configuration(object):
# Configure feature flags.
self.configure_compile_flags_exceptions()
self.configure_compile_flags_rtti()
+ self.configure_compile_flags_abi_version()
self.configure_compile_flags_no_global_filesystem_namespace()
self.configure_compile_flags_no_stdin()
self.configure_compile_flags_no_stdout()
@@ -440,6 +441,15 @@ class Configuration(object):
self.config.available_features.add('libcpp-no-rtti')
self.cxx.compile_flags += ['-fno-rtti', '-D_LIBCPP_NO_RTTI']
+ def configure_compile_flags_abi_version(self):
+ abi_version = self.get_lit_conf('abi_version', '').strip()
+ abi_unstable = self.get_lit_bool('abi_unstable')
+ if abi_version:
+ self.cxx.compile_flags += ['-D_LIBCPP_ABI_VERSION=' + abi_version]
+ if abi_unstable:
+ self.config.available_features.add('libcpp-abi-unstable')
+ self.cxx.compile_flags += ['-D_LIBCPP_ABI_UNSTABLE']
+
def configure_compile_flags_no_global_filesystem_namespace(self):
enable_global_filesystem_namespace = self.get_lit_bool(
'enable_global_filesystem_namespace', True)
Modified: libcxx/trunk/test/lit.site.cfg.in
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/lit.site.cfg.in?rev=250254&r1=250253&r2=250254&view=diff
==============================================================================
--- libcxx/trunk/test/lit.site.cfg.in (original)
+++ libcxx/trunk/test/lit.site.cfg.in Tue Oct 13 18:48:28 2015
@@ -7,6 +7,8 @@ config.enable_exceptions = "@LIBC
config.enable_rtti = "@LIBCXX_ENABLE_RTTI@"
config.enable_shared = "@LIBCXX_ENABLE_SHARED@"
config.enable_32bit = "@LIBCXX_BUILD_32_BITS@"
+config.abi_version = "@LIBCXX_ABI_VERSION@"
+config.abi_unstable = "@LIBCXX_ABI_UNSTABLE@"
config.enable_global_filesystem_namespace = "@LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE@"
config.enable_stdin = "@LIBCXX_ENABLE_STDIN@"
config.enable_stdout = "@LIBCXX_ENABLE_STDOUT@"
More information about the cfe-commits
mailing list