Tested powerpc64le-linux and by building a mips-none-elf cross with --disable-hosted-libstdcxx --without-headers (which fails currently).
Any objections? This fixes the --disable-hosted-libstdcxx build so that it works with --without-headers. Currently you need to also use --with-newlib, which is confusing for users who aren't actually using newlib. The AM_PROG_LIBTOOL checks are currently skipped for --with-newlib and --with-avrlibc builds, with this change they are also skipped when using --without-headers. It would be nice if using --disable-hosted-libstdcxx automatically skipped those checks, but GLIBCXX_ENABLE_HOSTED comes too late to make the AM_PROG_LIBTOOL checks depend on $is_hosted. The checks for EOF, SEEK_CUR etc. cause the build to fail if there is no <stdio.h> available. Unlike most headers, which get a HAVE_FOO_H macro, <stdio.h> is in autoconf's default includes, so every check tries to include it unconditionally. This change skips those checks for freestanding builds. Similarly, the checks for <stdint.h> types done by GCC_HEADER_STDINT try to include <stdio.h> and fail for --without-headers builds. This change skips the use of GCC_HEADER_STDINT for freestanding. We can probably stop using GCC_HEADER_STDINT entirely, since only one file uses the gstdint.h header that is generated, and that could easily be changed to use <stdint.h> instead. That can wait for stage 1. We also need to skip the GLIBCXX_CROSSCONFIG stage if --without-headers was used, since we don't have any of the functions it deals with. The end result of the changes above is that it should not be necessary for a --disable-hosted-libstdcxx --without-headers build to also use --with-newlib. Finally, compile libsupc++ with -ffreestanding when --without-headers is used, so that <stdint.h> will use <gcc-stdint.h> instead of expecting it to come from libc. libstdc++-v3/ChangeLog: PR libstdc++/103866 * acinclude.m4 (GLIBCXX_COMPUTE_STDIO_INTEGER_CONSTANTS): Do nothing for freestanding builds. (GLIBCXX_ENABLE_HOSTED): Define FREESTANDING_FLAGS. * configure.ac: Do not use AC_LIBTOOL_DLOPEN when configured with --without-headers. Do not use GCC_HEADER_STDINT for freestanding builds. * libsupc++/Makefile.am (HOSTED_CXXFLAGS): Use -ffreestanding for freestanding builds. * configure: Regenerate. * Makefile.in: Regenerate. * doc/Makefile.in: Regenerate. * include/Makefile.in: Regenerate. * libsupc++/Makefile.in: Regenerate. * po/Makefile.in: Regenerate. * python/Makefile.in: Regenerate. * src/Makefile.in: Regenerate. * src/c++11/Makefile.in: Regenerate. * src/c++17/Makefile.in: Regenerate. * src/c++20/Makefile.in: Regenerate. * src/c++98/Makefile.in: Regenerate. * src/filesystem/Makefile.in: Regenerate. * testsuite/Makefile.in: Regenerate. --- libstdc++-v3/Makefile.in | 1 + libstdc++-v3/acinclude.m4 | 8 ++++++ libstdc++-v3/configure | 35 ++++++++++++++++++------- libstdc++-v3/configure.ac | 10 +++++-- libstdc++-v3/doc/Makefile.in | 1 + libstdc++-v3/include/Makefile.in | 1 + libstdc++-v3/libsupc++/Makefile.am | 2 +- libstdc++-v3/libsupc++/Makefile.in | 3 ++- libstdc++-v3/po/Makefile.in | 1 + libstdc++-v3/python/Makefile.in | 1 + libstdc++-v3/src/Makefile.in | 1 + libstdc++-v3/src/c++11/Makefile.in | 1 + libstdc++-v3/src/c++17/Makefile.in | 1 + libstdc++-v3/src/c++20/Makefile.in | 1 + libstdc++-v3/src/c++98/Makefile.in | 1 + libstdc++-v3/src/filesystem/Makefile.in | 1 + libstdc++-v3/testsuite/Makefile.in | 1 + 17 files changed, 56 insertions(+), 14 deletions(-) diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4 index 635168d7e25..b770d5bcdc4 100644 --- a/libstdc++-v3/acinclude.m4 +++ b/libstdc++-v3/acinclude.m4 @@ -2081,6 +2081,7 @@ dnl Compute the EOF, SEEK_CUR, and SEEK_END integer constants. dnl AC_DEFUN([GLIBCXX_COMPUTE_STDIO_INTEGER_CONSTANTS], [ +if test "$is_hosted" = yes; then AC_CACHE_CHECK([for the value of EOF], glibcxx_cv_stdio_eof, [ AC_COMPUTE_INT([glibcxx_cv_stdio_eof], [[EOF]], [#include <stdio.h>], @@ -2104,6 +2105,7 @@ AC_DEFUN([GLIBCXX_COMPUTE_STDIO_INTEGER_CONSTANTS], [ ]) AC_DEFINE_UNQUOTED(_GLIBCXX_STDIO_SEEK_END, $glibcxx_cv_stdio_seek_end, [Define to the value of the SEEK_END integer constant.]) +fi ]) dnl @@ -2923,12 +2925,16 @@ AC_DEFUN([GLIBCXX_ENABLE_HOSTED], [ enable_hosted_libstdcxx=yes ;; esac]) + freestanding_flags= if test "$enable_hosted_libstdcxx" = no; then AC_MSG_NOTICE([Only freestanding libraries will be built]) is_hosted=no hosted_define=0 enable_abi_check=no enable_libstdcxx_pch=no + if test "x$with_headers" = xno; then + freestanding_flags="-ffreestanding" + fi else is_hosted=yes hosted_define=1 @@ -2936,6 +2942,8 @@ AC_DEFUN([GLIBCXX_ENABLE_HOSTED], [ GLIBCXX_CONDITIONAL(GLIBCXX_HOSTED, test $is_hosted = yes) AC_DEFINE_UNQUOTED(_GLIBCXX_HOSTED, $hosted_define, [Define to 1 if a full hosted library is built, or 0 if freestanding.]) + FREESTANDING_FLAGS="$freestanding_flags" + AC_SUBST(FREESTANDING_FLAGS) ]) diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac index 5b3c92f4bd7..827d770f444 100644 --- a/libstdc++-v3/configure.ac +++ b/libstdc++-v3/configure.ac @@ -90,7 +90,9 @@ AC_SYS_LARGEFILE GLIBCXX_CONFIGURE # Libtool setup. -if test "x${with_newlib}" != "xyes" && test "x${with_avrlibc}" != "xyes"; then +if test "x${with_newlib}" != "xyes" && + test "x${with_avrlibc}" != "xyes" && + test "x$with_headers" != "xno"; then AC_LIBTOOL_DLOPEN fi AM_PROG_LIBTOOL @@ -351,7 +353,7 @@ else AC_DEFINE(HAVE_ICONV) AC_DEFINE(HAVE_MEMALIGN) - else + elif test "x$with_headers" != "xno"; then GLIBCXX_CROSSCONFIG fi @@ -390,7 +392,11 @@ GCC_CHECK_UNWIND_GETIPINFO GCC_LINUX_FUTEX([AC_DEFINE(HAVE_LINUX_FUTEX, 1, [Define if futex syscall is available.])]) +if test "$is_hosted" = yes; then +# TODO: remove this and change src/c++11/compatibility-atomic-c++0x.cc to +# use <stdint.h> instead of <gstdint.h>. GCC_HEADER_STDINT(include/gstdint.h) +fi GLIBCXX_ENABLE_SYMVERS([yes]) AC_SUBST(libtool_VERSION) diff --git a/libstdc++-v3/libsupc++/Makefile.am b/libstdc++-v3/libsupc++/Makefile.am index 2a69a1cf677..65b5c1a87fd 100644 --- a/libstdc++-v3/libsupc++/Makefile.am +++ b/libstdc++-v3/libsupc++/Makefile.am @@ -139,7 +139,7 @@ atomicity.cc: ${atomicity_file} # as the occasion call for it. AM_CXXFLAGS = \ $(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \ - $(XTEMPLATE_FLAGS) \ + $(XTEMPLATE_FLAGS) $(FREESTANDING_FLAGS) \ $(WARN_CXXFLAGS) $(OPTIMIZE_CXXFLAGS) $(CONFIG_CXXFLAGS) AM_MAKEFLAGS = \