I forgot to say:
Tested x86_64-linux and aarch64-linux, built for avr, arm-eabi and
cris-elf.
Pushed to trunk.
On Fri, 8 Sept 2023 at 18:09, Jonathan Wakely via Libstdc++
<libstd...@gcc.gnu.org> wrote:
>
> This consolidates the three static archives for extensions into one, so
> that -lstdc++exp can be used to provide the definitions of all unstable
> library features.
>
> The libstdc++_libbacktrace.a archive is now just a "noinst" convenience
> library that is only used during the build, not installed. Its contents
> are added to libstdc++exp.a, along with the new non-inline definitions
> of std::stacktrace symbols.
>
> The libstdc++fs.a archive is still installed, but its contents are
> duplicated in libstdc++exp.a now. This means -lstdc++exp can be used
> instead of -lstdc++fs. For targets using the GNU linker we should
> consider replacing libstdc++fs.a with a linker script that does
> INPUT(libstdc++exp.a).
>
> The tests for <experimental/filesystem> could be changed to use
> -lstdc++exp instead of -lstdc++fs, which would allow removing
> src/filesystem/.libs from the LDFLAGS in scripts/testsuite_flags.in,
> but that can be done at a later date.
>
> libstdc++-v3/ChangeLog:
>
> * acinclude.m4 (GLIBCXX_CONFIGURE): Add c++23 directory.
> * configure: Regenerate.
> * doc/html/manual/*: Regenerate.
> * doc/xml/manual/using.xml: Update documentation on linking.
> * include/std/stacktrace: Remove declarations of libbacktrace
> APIs.
> (stacktrace_entry::_S_err_handler, stacktrace_entry::_S_init):
> Remove.
> (stacktrace_entry::_Info): New class.
> (stacktrace_entry::_M_get_info): Use _Info.
> (__stacktrace_impl): New class.
> (basic_stacktrace): Derive from __stacktrace_impl.
> (basic_stacktrace::current): Use __stacktrace_impl::_S_current.
> * scripts/testsuite_flags.in: Adjust LDFLAGS to find
> libstdc++exp instead of libstdc++_libbacktrace.
> * src/Makefile.am (SUBDIRS): Add c++23 directory.
> * src/Makefile.in: Regenerate.
> * src/c++20/Makefile.am: Fix comment.
> * src/c++20/Makefile.in: Regenerate.
> * src/c++23/Makefile.am: New file.
> * src/c++23/Makefile.in: New file.
> * src/c++23/stacktrace.cc: New file with definitions of
> stacktrace_entry::_Info and __stacktrace_impl members.
> * src/experimental/Makefile.am: Use LIBADD to include other
> libraries.
> * src/experimental/Makefile.in: Regenerate.
> * src/libbacktrace/Makefile.am: Use noinst_LTLIBRARIES.
> * src/libbacktrace/Makefile.in: Regenerate.
> * testsuite/19_diagnostics/stacktrace/current.cc: Adjust
> dg-options to use -lstdc++exp.
> * testsuite/19_diagnostics/stacktrace/entry.cc: Likewise.
> * testsuite/19_diagnostics/stacktrace/stacktrace.cc: Likewise.
> * testsuite/23_containers/vector/debug/assign4_backtrace_neg.cc:
> Likewise.
> ---
> libstdc++-v3/acinclude.m4 | 2 +-
> libstdc++-v3/configure | 16 +-
> libstdc++-v3/doc/html/manual/using.html | 26 +-
> .../html/manual/using_dynamic_or_shared.html | 4 +
> libstdc++-v3/doc/xml/manual/using.xml | 37 +-
> libstdc++-v3/include/std/stacktrace | 144 +---
> libstdc++-v3/scripts/testsuite_flags.in | 8 +-
> libstdc++-v3/src/Makefile.am | 4 +-
> libstdc++-v3/src/Makefile.in | 7 +-
> libstdc++-v3/src/c++20/Makefile.am | 2 +-
> libstdc++-v3/src/c++20/Makefile.in | 2 +-
> libstdc++-v3/src/c++23/Makefile.am | 109 +++
> libstdc++-v3/src/c++23/Makefile.in | 747 ++++++++++++++++++
> libstdc++-v3/src/c++23/stacktrace.cc | 171 ++++
> libstdc++-v3/src/experimental/Makefile.am | 20 +
> libstdc++-v3/src/experimental/Makefile.in | 15 +-
> libstdc++-v3/src/libbacktrace/Makefile.am | 3 +-
> libstdc++-v3/src/libbacktrace/Makefile.in | 88 +--
> .../19_diagnostics/stacktrace/current.cc | 2 +-
> .../19_diagnostics/stacktrace/entry.cc | 2 +-
> .../19_diagnostics/stacktrace/stacktrace.cc | 2 +-
> .../vector/debug/assign4_backtrace_neg.cc | 2 +-
> 22 files changed, 1185 insertions(+), 228 deletions(-)
> create mode 100644 libstdc++-v3/src/c++23/Makefile.am
> create mode 100644 libstdc++-v3/src/c++23/Makefile.in
> create mode 100644 libstdc++-v3/src/c++23/stacktrace.cc
>
> diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
> index fcf79503265..34faa3c049f 100644
> --- a/libstdc++-v3/acinclude.m4
> +++ b/libstdc++-v3/acinclude.m4
> @@ -49,7 +49,7 @@ AC_DEFUN([GLIBCXX_CONFIGURE], [
> # Keep these sync'd with the list in Makefile.am. The first provides an
> # expandable list at autoconf time; the second provides an expandable list
> # (i.e., shell variable) at configure time.
> - m4_define([glibcxx_SUBDIRS],[include libsupc++ src src/c++98 src/c++11
> src/c++17 src/c++20 src/filesystem src/libbacktrace src/experimental doc po
> testsuite python])
> + m4_define([glibcxx_SUBDIRS],[include libsupc++ src src/c++98 src/c++11
> src/c++17 src/c++20 src/c++23 src/filesystem src/libbacktrace
> src/experimental doc po testsuite python])
> SUBDIRS='glibcxx_SUBDIRS'
>
> # These need to be absolute paths, yet at the same time need to
> diff --git a/libstdc++-v3/doc/xml/manual/using.xml
> b/libstdc++-v3/doc/xml/manual/using.xml
> index 3a507fc1671..7276cad0feb 100644
> --- a/libstdc++-v3/doc/xml/manual/using.xml
> +++ b/libstdc++-v3/doc/xml/manual/using.xml
> @@ -100,30 +100,27 @@
> </entry>
> </row>
>
> - <row>
> - <entry><literal>-lstdc++fs</literal></entry>
> - <entry>Linking to <filename class="libraryfile">libstdc++fs</filename>
> - is required for use of the Filesystem library extensions in
> - <filename
> class="headerfile"><experimental/filesystem></filename>.
> - </entry>
> - </row>
> -
> <row>
> <entry><literal>-lstdc++exp</literal></entry>
> - <entry>Linking to <filename class="libraryfile">libstdc++exp</filename>
> - is required for use of the C++ Contracts extensions enabled by
> - <literal>-fcontracts</literal>.
> + <entry>Linking to <filename
> class="libraryfile">libstdc++exp.a</filename>
> + is required for use of experimental C++ library features.
> + This currently provides support for the C++23 types defined in the
> + <filename class="headerfile"><stacktrace></filename> header,
> + the Filesystem library extensions defined in the
> + <filename
> class="headerfile"><experimental/filesystem></filename>
> + header,
> + and the Contracts extensions enabled by
> <literal>-fcontracts</literal>.
> </entry>
> </row>
>
> <row>
> - <entry><literal>-lstdc++_libbacktrace</literal></entry>
> - <entry>Until C++23 support is non-experimental, linking to
> - <filename class="libraryfile">libstdc++_libbacktrace.a</filename>
> - is required for use of the C++23 type
> - <classname>std::stacktrace</classname>
> - and related types in
> - <filename class="headerfile"><stacktrace></filename>.
> + <entry><literal>-lstdc++fs</literal></entry>
> + <entry>Linking to <filename
> class="libraryfile">libstdc++fs.a</filename>
> + is another way to use the Filesystem library extensions defined in
> the
> + <filename
> class="headerfile"><experimental/filesystem></filename>
> + header.
> + The <filename class="libraryfile">libstdc++exp.a</filename> library
> + also provides all the symbols contained in this library.
> </entry>
> </row>
>
> @@ -1710,6 +1707,10 @@ A quick read of the relevant part of the GCC
> and link with <option>-lstdc++fs</option>. The library implementation
> is incomplete on non-POSIX platforms, specifically Windows is only
> partially supported.
> + Since GCC 14, <filename class="libraryfile">libstdc++exp.a</filename>
> + also contains the definitions for this library,
> + so <option>-lstdc++exp</option> can be used instead of
> + <option>-lstdc++fs</option>.
> </para>
>
> <para>
> diff --git a/libstdc++-v3/include/std/stacktrace
> b/libstdc++-v3/include/std/stacktrace
> index 07949e70861..358a81b82e5 100644
> --- a/libstdc++-v3/include/std/stacktrace
> +++ b/libstdc++-v3/include/std/stacktrace
> @@ -45,43 +45,6 @@
> #include <bits/stl_uninitialized.h>
> #include <ext/numeric_traits.h>
>
> -struct __glibcxx_backtrace_state;
> -struct __glibcxx_backtrace_simple_data;
> -
> -extern "C"
> -{
> -__glibcxx_backtrace_state*
> -__glibcxx_backtrace_create_state(const char*, int,
> - void(*)(void*, const char*, int),
> - void*);
> -
> -int
> -__glibcxx_backtrace_simple(__glibcxx_backtrace_state*, int,
> - int (*) (void*, __UINTPTR_TYPE__),
> - void(*)(void*, const char*, int),
> - void*);
> -int
> -__glibcxx_backtrace_pcinfo(__glibcxx_backtrace_state*, __UINTPTR_TYPE__,
> - int (*)(void*, __UINTPTR_TYPE__,
> - const char*, int, const char*),
> - void(*)(void*, const char*, int),
> - void*);
> -
> -int
> -__glibcxx_backtrace_syminfo(__glibcxx_backtrace_state*, __UINTPTR_TYPE__
> addr,
> - void (*) (void*, __UINTPTR_TYPE__, const char*,
> - __UINTPTR_TYPE__, __UINTPTR_TYPE__),
> - void(*)(void*, const char*, int),
> - void*);
> -}
> -
> -namespace __cxxabiv1
> -{
> - extern "C" char*
> - __cxa_demangle(const char* __mangled_name, char* __output_buffer,
> - size_t* __length, int* __status);
> -}
> -
> namespace std _GLIBCXX_VISIBILITY(default)
> {
> _GLIBCXX_BEGIN_NAMESPACE_VERSION
> @@ -156,80 +119,53 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>
> template<typename _Allocator> friend class basic_stacktrace;
>
> - static void _S_err_handler(void*, const char*, int) { }
> -
> - static __glibcxx_backtrace_state*
> - _S_init()
> - {
> - static __glibcxx_backtrace_state* __state
> - = __glibcxx_backtrace_create_state(nullptr, 1, _S_err_handler,
> nullptr);
> - return __state;
> - }
> -
> friend ostream&
> operator<<(ostream&, const stacktrace_entry&);
>
> + // Type-erased wrapper for the fields of a stacktrace entry.
> + // This type is independent of which std::string ABI is in use.
> + struct _Info
> + {
> + void* _M_desc;
> + void* _M_file;
> + int* _M_line;
> + void (*_M_set)(void*, const char*);
> +
> + _GLIBCXX_DEFAULT_ABI_TAG
> + static void
> + _S_set(void* __dest, const char* __str)
> + { static_cast<string*>(__dest)->assign(__str); }
> +
> + _Info(string* __desc, string* __file, int* __line)
> + : _M_desc(__desc), _M_file(__file), _M_line(__line), _M_set(_S_set)
> + { }
> +
> + bool
> + _M_populate(native_handle_type);
> +
> + void _M_set_file(const char*);
> + void _M_set_desc(const char*);
> + };
> +
> bool
> _M_get_info(string* __desc, string* __file, int* __line) const
> {
> if (!*this)
> return false;
> -
> - struct _Data
> - {
> - string* _M_desc;
> - string* _M_file;
> - int* _M_line;
> - } __data = { __desc, __file, __line };
> -
> - auto __cb = [](void* __data, uintptr_t, const char* __filename,
> - int __lineno, const char* __function) -> int {
> - auto& __d = *static_cast<_Data*>(__data);
> - if (__function && __d._M_desc)
> - *__d._M_desc = _S_demangle(__function);
> - if (__filename && __d._M_file)
> - *__d._M_file = __filename;
> - if (__d._M_line)
> - *__d._M_line = __lineno;
> - return __function != nullptr;
> - };
> - const auto __state = _S_init();
> - if (::__glibcxx_backtrace_pcinfo(__state, _M_pc, +__cb, _S_err_handler,
> - &__data))
> - return true;
> - if (__desc && __desc->empty())
> - {
> - auto __cb2 = [](void* __data, uintptr_t, const char* __symname,
> - uintptr_t, uintptr_t) {
> - if (__symname)
> - *static_cast<_Data*>(__data)->_M_desc =
> _S_demangle(__symname);
> - };
> - if (::__glibcxx_backtrace_syminfo(__state, _M_pc, +__cb2,
> - _S_err_handler, &__data))
> - return true;
> - }
> - return false;
> + return _Info(__desc, __file, __line)._M_populate(_M_pc);
> }
> + };
>
> - static string
> - _S_demangle(const char* __name)
> - {
> - string __s;
> - int __status;
> - char* __str = __cxxabiv1::__cxa_demangle(__name, nullptr, nullptr,
> - &__status);
> - if (__status == 0)
> - __s = __str;
> - else
> - __s = __name;
> - __builtin_free(__str);
> - return __s;
> - }
> + class __stacktrace_impl
> + {
> + protected:
> + static int _S_current(int (*) (void*, __UINTPTR_TYPE__), void*, int = 0);
> };
>
> // [stacktrace.basic], class template basic_stacktrace
> template<typename _Allocator>
> class basic_stacktrace
> + : private __stacktrace_impl
> {
> using _AllocTraits = allocator_traits<_Allocator>;
> using uintptr_t = __UINTPTR_TYPE__;
> @@ -256,10 +192,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> basic_stacktrace __ret(__alloc);
> if (auto __cb = __ret._M_prepare()) [[likely]]
> {
> - auto __state = stacktrace_entry::_S_init();
> - if (__glibcxx_backtrace_simple(__state, 1, __cb,
> - stacktrace_entry::_S_err_handler,
> - std::__addressof(__ret)))
> + if (_S_current(__cb, std::__addressof(__ret)))
> __ret._M_clear();
> }
> return __ret;
> @@ -275,10 +208,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> return __ret;
> if (auto __cb = __ret._M_prepare()) [[likely]]
> {
> - auto __state = stacktrace_entry::_S_init();
> - if (__glibcxx_backtrace_simple(__state, __skip + 1, __cb,
> - stacktrace_entry::_S_err_handler,
> - std::__addressof(__ret)))
> + if (_S_current(__cb, std::__addressof(__ret), __skip))
> __ret._M_clear();
> }
>
> @@ -299,11 +229,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> return __ret;
> if (auto __cb = __ret._M_prepare(__max_depth)) [[likely]]
> {
> - auto __state = stacktrace_entry::_S_init();
> - int __err = __glibcxx_backtrace_simple(__state, __skip + 1, __cb,
> -
> stacktrace_entry::_S_err_handler,
> - std::__addressof(__ret));
> - if (__err < 0)
> + if (_S_current(__cb, std::__addressof(__ret), __skip) < 0)
> __ret._M_clear();
> else if (__ret.size() > __max_depth)
> {
> diff --git a/libstdc++-v3/scripts/testsuite_flags.in
> b/libstdc++-v3/scripts/testsuite_flags.in
> index 18748f0f9ce..8bf4918287a 100755
> --- a/libstdc++-v3/scripts/testsuite_flags.in
> +++ b/libstdc++-v3/scripts/testsuite_flags.in
> @@ -78,14 +78,14 @@ case ${query} in
> ;;
> --cxxldflags)
> FS_LDFLAGS=
> - BT_LDFLAGS=
> + EXP_LDFLAGS=
> if [ -d ${BUILD_DIR}/src/filesystem/.libs ]; then
> FS_LDFLAGS=-L${BUILD_DIR}/src/filesystem/.libs
> fi
> - if [ -d ${BUILD_DIR}/src/libbacktrace/.libs ]; then
> - BT_LDFLAGS=-L${BUILD_DIR}/src/libbacktrace/.libs
> + if [ -d ${BUILD_DIR}/src/experimental/.libs ]; then
> + EXP_LDFLAGS=-L${BUILD_DIR}/src/experimental/.libs
> fi
> - SECTIONLDFLAGS="@SECTION_LDFLAGS@ @LIBICONV@ $FS_LDFLAGS $BT_LDFLAGS"
> + SECTIONLDFLAGS="@SECTION_LDFLAGS@ @LIBICONV@ $FS_LDFLAGS $EXP_LDFLAGS"
> echo ${SECTIONLDFLAGS}
> ;;
> *)
> diff --git a/libstdc++-v3/src/Makefile.am b/libstdc++-v3/src/Makefile.am
> index 5b9af41cdb9..32de5304122 100644
> --- a/libstdc++-v3/src/Makefile.am
> +++ b/libstdc++-v3/src/Makefile.am
> @@ -43,7 +43,8 @@ experimental_dir =
> endif
>
> ## Keep this list sync'd with acinclude.m4:GLIBCXX_CONFIGURE.
> -SUBDIRS = c++98 c++11 c++17 c++20 $(filesystem_dir) $(backtrace_dir)
> $(experimental_dir)
> +SUBDIRS = c++98 c++11 c++17 c++20 c++23 \
> + $(filesystem_dir) $(backtrace_dir) $(experimental_dir)
>
> # Cross compiler support.
> if VTV_CYGMIN
> @@ -75,6 +76,7 @@ vpath % $(top_srcdir)/src/c++98
> vpath % $(top_srcdir)/src/c++11
> vpath % $(top_srcdir)/src/c++17
> vpath % $(top_srcdir)/src/c++20
> +vpath % $(top_srcdir)/src/c++23
> if ENABLE_FILESYSTEM_TS
> vpath % $(top_srcdir)/src/filesystem
> endif
> diff --git a/libstdc++-v3/src/c++20/Makefile.am
> b/libstdc++-v3/src/c++20/Makefile.am
> index 0bc8a7b832a..e947855e6ae 100644
> --- a/libstdc++-v3/src/c++20/Makefile.am
> +++ b/libstdc++-v3/src/c++20/Makefile.am
> @@ -22,7 +22,7 @@
>
> include $(top_srcdir)/fragment.am
>
> -# Convenience library for C++17 runtime.
> +# Convenience library for C++20 runtime.
> noinst_LTLIBRARIES = libc++20convenience.la
>
> headers =
> diff --git a/libstdc++-v3/src/c++23/Makefile.am
> b/libstdc++-v3/src/c++23/Makefile.am
> new file mode 100644
> index 00000000000..da988c352f8
> --- /dev/null
> +++ b/libstdc++-v3/src/c++23/Makefile.am
> @@ -0,0 +1,109 @@
> +## Makefile for the C++23 sources of the GNU C++ Standard library.
> +##
> +## Copyright (C) 1997-2023 Free Software Foundation, Inc.
> +##
> +## This file is part of the libstdc++ version 3 distribution.
> +## Process this file with automake to produce Makefile.in.
> +
> +## This file is part of the GNU ISO C++ Library. This library is free
> +## software; you can redistribute it and/or modify it under the
> +## terms of the GNU General Public License as published by the
> +## Free Software Foundation; either version 3, or (at your option)
> +## any later version.
> +
> +## This library is distributed in the hope that it will be useful,
> +## but WITHOUT ANY WARRANTY; without even the implied warranty of
> +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> +## GNU General Public License for more details.
> +
> +## You should have received a copy of the GNU General Public License along
> +## with this library; see the file COPYING3. If not see
> +## <http://www.gnu.org/licenses/>.
> +
> +include $(top_srcdir)/fragment.am
> +
> +# Convenience library for C++23 runtime.
> +noinst_LTLIBRARIES = libc++23convenience.la
> +
> +headers =
> +
> +if ENABLE_EXTERN_TEMPLATE
> +# XTEMPLATE_FLAGS = -fno-implicit-templates
> +inst_sources =
> +else
> +# XTEMPLATE_FLAGS =
> +inst_sources =
> +endif
> +
> +sources = stacktrace.cc
> +
> +vpath % $(top_srcdir)/src/c++23
> +
> +
> +if GLIBCXX_HOSTED
> +libc__23convenience_la_SOURCES = $(sources) $(inst_sources)
> +else
> +libc__23convenience_la_SOURCES =
> +endif
> +
> +# AM_CXXFLAGS needs to be in each subdirectory so that it can be
> +# modified in a per-library or per-sub-library way. Need to manually
> +# set this option because CONFIG_CXXFLAGS has to be after
> +# OPTIMIZE_CXXFLAGS on the compile line so that -O2 can be overridden
> +# as the occasion calls for it.
> +AM_CXXFLAGS = \
> + -std=gnu++23 \
> + $(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
> + $(XTEMPLATE_FLAGS) $(VTV_CXXFLAGS) \
> + $(WARN_CXXFLAGS) $(OPTIMIZE_CXXFLAGS) $(CONFIG_CXXFLAGS) \
> + -fimplicit-templates
> +
> +AM_MAKEFLAGS = \
> + "gxx_include_dir=$(gxx_include_dir)"
> +
> +# Libtool notes
> +
> +# 1) In general, libtool expects an argument such as `--tag=CXX' when
> +# using the C++ compiler, because that will enable the settings
> +# detected when C++ support was being configured. However, when no
> +# such flag is given in the command line, libtool attempts to figure
> +# it out by matching the compiler name in each configuration section
> +# against a prefix of the command line. The problem is that, if the
> +# compiler name and its initial flags stored in the libtool
> +# configuration file don't match those in the command line, libtool
> +# can't decide which configuration to use, and it gives up. The
> +# correct solution is to add `--tag CXX' to LTCXXCOMPILE and maybe
> +# CXXLINK, just after $(LIBTOOL), so that libtool doesn't have to
> +# attempt to infer which configuration to use.
> +#
> +# The second tag argument, `--tag disable-shared` means that libtool
> +# only compiles each source once, for static objects. In actuality,
> +# glibcxx_lt_pic_flag and glibcxx_compiler_shared_flag are added to
> +# the libtool command that is used create the object, which is
> +# suitable for shared libraries. The `--tag disable-shared` must be
> +# placed after --tag CXX lest things CXX undo the affect of
> +# disable-shared.
> +
> +# 2) Need to explicitly set LTCXXCOMPILE so that EXTRA_CXX_FLAGS is
> +# last. (That way, things like -O2 passed down from the toplevel can
> +# be overridden by --enable-debug.)
> +LTCXXCOMPILE = \
> + $(LIBTOOL) --tag CXX --tag disable-shared \
> + $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
> + --mode=compile $(CXX) $(TOPLEVEL_INCLUDES) \
> + $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CXXFLAGS) $(CXXFLAGS)
> $(EXTRA_CXX_FLAGS)
> +
> +LTLDFLAGS = $(shell $(SHELL) $(top_srcdir)/../libtool-ldflags $(LDFLAGS))
> +
> +# 3) We'd have a problem when building the shared libstdc++ object if
> +# the rules automake generates would be used. We cannot allow g++ to
> +# be used since this would add -lstdc++ to the link line which of
> +# course is problematic at this point. So, we get the top-level
> +# directory to configure libstdc++-v3 to use gcc as the C++
> +# compilation driver.
> +CXXLINK = \
> + $(LIBTOOL) --tag CXX --tag disable-shared \
> + $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
> + --mode=link $(CXX) \
> + $(VTV_CXXLINKFLAGS) \
> + $(OPT_LDFLAGS) $(SECTION_LDFLAGS) $(AM_CXXFLAGS) $(LTLDFLAGS) -o $@
> diff --git a/libstdc++-v3/src/c++23/stacktrace.cc
> b/libstdc++-v3/src/c++23/stacktrace.cc
> new file mode 100644
> index 00000000000..10cfa44e4f5
> --- /dev/null
> +++ b/libstdc++-v3/src/c++23/stacktrace.cc
> @@ -0,0 +1,171 @@
> +// Implementation of <stacktrace> -*- C++ -*-
> +
> +// Copyright The GNU Toolchain Authors.
> +//
> +// This file is part of the GNU ISO C++ Library. This library is free
> +// software; you can redistribute it and/or modify it under the
> +// terms of the GNU General Public License as published by the
> +// Free Software Foundation; either version 3.
> +
> +// This library is distributed in the hope that it will be useful,
> +// but WITHOUT ANY WARRANTY; without even the implied warranty of
> +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> +// GNU General Public License for more details.
> +
> +// Under Section 7 of GPL version 3, you are granted additional
> +// permissions described in the GCC Runtime Library Exception, version
> +// 3.1, as published by the Free Software Foundation.
> +
> +// You should have received a copy of the GNU General Public License and
> +// a copy of the GCC Runtime Library Exception along with this program;
> +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
> +// <http://www.gnu.org/licenses/>.
> +
> +#include <stacktrace>
> +#include <cstdlib>
> +
> +#ifdef __cpp_lib_stacktrace // C++ >= 23 && hosted && HAVE_STACKTRACE
> +struct __glibcxx_backtrace_state;
> +
> +extern "C"
> +{
> +__glibcxx_backtrace_state*
> +__glibcxx_backtrace_create_state(const char*, int,
> + void(*)(void*, const char*, int),
> + void*);
> +
> +int
> +__glibcxx_backtrace_simple(__glibcxx_backtrace_state*, int,
> + int (*) (void*, __UINTPTR_TYPE__),
> + void(*)(void*, const char*, int),
> + void*);
> +int
> +__glibcxx_backtrace_pcinfo(__glibcxx_backtrace_state*, __UINTPTR_TYPE__,
> + int (*)(void*, __UINTPTR_TYPE__,
> + const char*, int, const char*),
> + void(*)(void*, const char*, int),
> + void*);
> +
> +int
> +__glibcxx_backtrace_syminfo(__glibcxx_backtrace_state*, __UINTPTR_TYPE__
> addr,
> + void (*) (void*, __UINTPTR_TYPE__, const char*,
> + __UINTPTR_TYPE__, __UINTPTR_TYPE__),
> + void(*)(void*, const char*, int),
> + void*);
> +}
> +
> +namespace __cxxabiv1
> +{
> + extern "C" char*
> + __cxa_demangle(const char* mangled_name, char* output_buffer, size_t*
> length,
> + int* status);
> +}
> +
> +namespace std
> +{
> +namespace
> +{
> + char*
> + demangle(const char* name)
> + {
> + int status;
> + char* str = __cxxabiv1::__cxa_demangle(name, nullptr, nullptr, &status);
> + if (status == 0)
> + return str;
> + else
> + {
> + std::free(str);
> + return nullptr;
> + }
> + }
> +
> + void
> + err_handler(void*, const char*, int)
> + { }
> +
> + __glibcxx_backtrace_state*
> + init()
> + {
> +#if __GTHREADS && ! defined(__cpp_threadsafe_static_init)
> +# warning "std::stacktrace initialization will not be thread-safe"
> +#endif
> + static __glibcxx_backtrace_state* state
> + = __glibcxx_backtrace_create_state(nullptr, 1, err_handler, nullptr);
> + return state;
> + }
> +}
> +
> +void
> +stacktrace_entry::_Info::_M_set_file(const char* filename)
> +{
> + if (filename && _M_file)
> + _M_set(_M_file, filename);
> +}
> +
> +void
> +stacktrace_entry::_Info::_M_set_desc(const char* function)
> +{
> + if (function && _M_desc)
> + {
> + if (char* s = demangle(function))
> + {
> + _M_set(_M_desc, s);
> + std::free(s);
> + }
> + else
> + _M_set(_M_desc, function);
> + }
> +}
> +
> +#pragma GCC diagnostic push
> +// The closure types below don't escape so we don't care about their
> mangling.
> +#pragma GCC diagnostic ignored "-Wabi"
> +bool
> +stacktrace_entry::_Info::_M_populate(native_handle_type pc)
> +{
> + auto cb = [](void* self, uintptr_t, const char* filename, int lineno,
> + const char* function) -> int
> + {
> + auto& info = *static_cast<_Info*>(self);
> + info._M_set_desc(function);
> + info._M_set_file(filename);
> + if (info._M_line)
> + *info._M_line = lineno;
> + return function != nullptr;
> + };
> + const auto state = init();
> + if (::__glibcxx_backtrace_pcinfo(state, pc, +cb, err_handler, this))
> + return true;
> +
> + // If we get here then backtrace_pcinfo did not give us a function name.
> + // If the caller wanted a function name, try again using backtrace_syminfo.
> + if (_M_desc)
> + {
> + auto cb2 = [](void* self, uintptr_t, const char* symname,
> + uintptr_t, uintptr_t)
> + {
> + static_cast<_Info*>(self)->_M_set_desc(symname);
> + };
> + if (::__glibcxx_backtrace_syminfo(state, pc, +cb2, err_handler, this))
> + return true;
> + }
> + return false;
> +}
> +#pragma GCC diagnostic pop
> +
> +// Ensure no tail-call optimization, so that this frame isn't reused for the
> +// backtrace_simple call, so that the number of frames to skip doesn't vary.
> +[[gnu::optimize("no-optimize-sibling-calls")]]
> +int
> +__stacktrace_impl::_S_current(int (*cb) (void*, __UINTPTR_TYPE__), void* obj,
> + int skip)
> +{
> + const auto state = init();
> + // skip+2 because we don't want this function or its caller to be included.
> + int r = ::__glibcxx_backtrace_simple(state, skip + 2, cb, err_handler,
> obj);
> + // Could also use this to prevent tail-call optim: __asm ("" : "+g" (r));
> + return r;
> +}
> +
> +}
> +#endif
> diff --git a/libstdc++-v3/src/experimental/Makefile.am
> b/libstdc++-v3/src/experimental/Makefile.am
> index 3b962e7d804..a61465f4eaf 100644
> --- a/libstdc++-v3/src/experimental/Makefile.am
> +++ b/libstdc++-v3/src/experimental/Makefile.am
> @@ -24,6 +24,18 @@ include $(top_srcdir)/fragment.am
>
> toolexeclib_LTLIBRARIES = libstdc++exp.la
>
> +if ENABLE_FILESYSTEM_TS
> +filesystem_lib = $(top_builddir)/src/filesystem/libstdc++fs.la
> +else
> +filesystem_lib =
> +endif
> +
> +if ENABLE_BACKTRACE
> +backtrace_lib = $(top_builddir)/src/libbacktrace/libstdc++_libbacktrace.la
> +else
> +backtrace_lib =
> +endif
> +
> headers =
>
> sources = \
> @@ -33,6 +45,14 @@ sources = \
>
> libstdc__exp_la_SOURCES = $(sources)
>
> +libstdc__exp_la_LIBADD = \
> + $(top_builddir)/src/c++23/libc++23convenience.la \
> + $(filesystem_lib) $(backtrace_lib)
> +
> +libstdc__exp_la_DEPENDENCIES = \
> + $(top_builddir)/src/c++23/libc++23convenience.la \
> + $(filesystem_lib) $(backtrace_lib)
> +
> # AM_CXXFLAGS needs to be in each subdirectory so that it can be
> # modified in a per-library or per-sub-library way. Need to manually
> # set this option because CONFIG_CXXFLAGS has to be after
> diff --git a/libstdc++-v3/src/libbacktrace/Makefile.am
> b/libstdc++-v3/src/libbacktrace/Makefile.am
> index 27c1ea570e0..492d3b6e952 100644
> --- a/libstdc++-v3/src/libbacktrace/Makefile.am
> +++ b/libstdc++-v3/src/libbacktrace/Makefile.am
> @@ -31,7 +31,8 @@
>
> include $(top_srcdir)/fragment.am
>
> -toolexeclib_LTLIBRARIES = libstdc++_libbacktrace.la
> +# Convenience library for C++23 runtime.
> +noinst_LTLIBRARIES = libstdc++_libbacktrace.la
>
> ACLOCAL_AMFLAGS = -I ../.. -I ../../config
>
> diff --git a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/current.cc
> b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/current.cc
> index 184e23b460e..f6c860fc7a4 100644
> --- a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/current.cc
> +++ b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/current.cc
> @@ -1,4 +1,4 @@
> -// { dg-options "-std=gnu++23 -lstdc++_libbacktrace" }
> +// { dg-options "-std=gnu++23 -lstdc++exp" }
> // { dg-do run { target c++23 } }
> // { dg-require-effective-target stacktrace }
>
> diff --git a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/entry.cc
> b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/entry.cc
> index a222c425b20..f0406953d03 100644
> --- a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/entry.cc
> +++ b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/entry.cc
> @@ -1,4 +1,4 @@
> -// { dg-options "-std=gnu++23 -lstdc++_libbacktrace" }
> +// { dg-options "-std=gnu++23 -lstdc++exp" }
> // { dg-do run { target c++23 } }
> // { dg-require-effective-target stacktrace }
>
> diff --git a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/stacktrace.cc
> b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/stacktrace.cc
> index 8dfdf4739be..0a358b7b8ff 100644
> --- a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/stacktrace.cc
> +++ b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/stacktrace.cc
> @@ -1,4 +1,4 @@
> -// { dg-options "-std=gnu++23 -lstdc++_libbacktrace" }
> +// { dg-options "-std=gnu++23 -lstdc++exp" }
> // { dg-do run { target c++23 } }
> // { dg-require-effective-target stacktrace }
>
> diff --git
> a/libstdc++-v3/testsuite/23_containers/vector/debug/assign4_backtrace_neg.cc
> b/libstdc++-v3/testsuite/23_containers/vector/debug/assign4_backtrace_neg.cc
> index 520788d5cb7..43a82fb1201 100644
> ---
> a/libstdc++-v3/testsuite/23_containers/vector/debug/assign4_backtrace_neg.cc
> +++
> b/libstdc++-v3/testsuite/23_containers/vector/debug/assign4_backtrace_neg.cc
> @@ -1,5 +1,5 @@
> // { dg-do run { xfail *-*-* } }
> -// { dg-options "-D_GLIBCXX_DEBUG_BACKTRACE -lstdc++_libbacktrace" }
> +// { dg-options "-D_GLIBCXX_DEBUG_BACKTRACE -lstdc++exp" }
> // { dg-require-effective-target stacktrace }
>
> #include <debug/vector>
> --
> 2.41.0
>
