libstdc++: Fix and simplify freestanding configuration [PR103866]

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.
2022-01-06 13:54:53 +00:00 · 2022-01-06 13:54:53 +00:00 · 68c2e9e923
parent e54dda45f9
commit 68c2e9e923
17 changed files with 56 additions and 14 deletions
--- a/libstdc++-v3/Makefile.in
+++ b/libstdc++-v3/Makefile.in
@ -240,6 +240,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- 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)
 ])


--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@ -771,6 +771,7 @@ thread_header
 glibcxx_PCHFLAGS
 GLIBCXX_BUILD_PCH_FALSE
 GLIBCXX_BUILD_PCH_TRUE
+FREESTANDING_FLAGS
 GLIBCXX_HOSTED_FALSE
 GLIBCXX_HOSTED_TRUE
 glibcxx_compiler_shared_flag
@ -5949,7 +5950,9 @@ $as_echo "$as_me: OS config directory is $os_include_dir" >&6;}


 # 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
  enable_dlopen=yes


@ -12176,7 +12179,7 @@ else
  lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
  lt_status=$lt_dlunknown
  cat > conftest.$ac_ext <<_LT_EOF
-#line 12179 "configure"
+#line 12182 "configure"
 #include "confdefs.h"

 #if HAVE_DLFCN_H
@ -12282,7 +12285,7 @@ else
  lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
  lt_status=$lt_dlunknown
  cat > conftest.$ac_ext <<_LT_EOF
-#line 12285 "configure"
+#line 12288 "configure"
 #include "confdefs.h"

 #if HAVE_DLFCN_H
@ -15623,6 +15626,7 @@ else
     esac
 fi

+  freestanding_flags=
  if test "$enable_hosted_libstdcxx" = no; then
    { $as_echo "$as_me:${as_lineno-$LINENO}: Only freestanding libraries will be built" >&5
 $as_echo "$as_me: Only freestanding libraries will be built" >&6;}
@ -15630,6 +15634,9 @@ $as_echo "$as_me: Only freestanding libraries will be built" >&6;}
    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
@ -15640,6 +15647,8 @@ cat >>confdefs.h <<_ACEOF
 #define _GLIBCXX_HOSTED $hosted_define
 _ACEOF

+  FREESTANDING_FLAGS="$freestanding_flags"
+


 # Enable descriptive messages to standard output on termination.
@ -15960,7 +15969,7 @@ $as_echo "$glibcxx_cv_atomic_long_long" >&6; }
  # Fake what AC_TRY_COMPILE does.

    cat > conftest.$ac_ext << EOF
-#line 15963 "configure"
+#line 15972 "configure"
 int main()
 {
  typedef bool atomic_type;
@ -15995,7 +16004,7 @@ $as_echo "$glibcxx_cv_atomic_bool" >&6; }
    rm -f conftest*

    cat > conftest.$ac_ext << EOF
-#line 15998 "configure"
+#line 16007 "configure"
 int main()
 {
  typedef short atomic_type;
@ -16030,7 +16039,7 @@ $as_echo "$glibcxx_cv_atomic_short" >&6; }
    rm -f conftest*

    cat > conftest.$ac_ext << EOF
-#line 16033 "configure"
+#line 16042 "configure"
 int main()
 {
  // NB: _Atomic_word not necessarily int.
@ -16066,7 +16075,7 @@ $as_echo "$glibcxx_cv_atomic_int" >&6; }
    rm -f conftest*

    cat > conftest.$ac_ext << EOF
-#line 16069 "configure"
+#line 16078 "configure"
 int main()
 {
  typedef long long atomic_type;
@ -16219,7 +16228,7 @@ $as_echo "mutex" >&6; }
  # unnecessary for this test.

    cat > conftest.$ac_ext << EOF
-#line 16222 "configure"
+#line 16231 "configure"
 int main()
 {
  _Decimal32 d1;
@ -16261,7 +16270,7 @@ ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
  # unnecessary for this test.

  cat > conftest.$ac_ext << EOF
-#line 16264 "configure"
+#line 16273 "configure"
 template<typename T1, typename T2>
  struct same
  { typedef T2 type; };
@ -20183,6 +20192,7 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 # For the EOF, SEEK_CUR, and SEEK_END integer constants.


+if test "$is_hosted" = yes; then
  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for the value of EOF" >&5
 $as_echo_n "checking for the value of EOF... " >&6; }
 if ${glibcxx_cv_stdio_eof+:} false; then :
@ -20248,6 +20258,7 @@ cat >>confdefs.h <<_ACEOF
 #define _GLIBCXX_STDIO_SEEK_END $glibcxx_cv_stdio_seek_end
 _ACEOF

+fi


 # For gettimeofday support.
@ -29129,7 +29140,7 @@ else

    $as_echo "#define HAVE_MEMALIGN 1" >>confdefs.h

-  else
+  elif test "x$with_headers" != "xno"; then

 # Base decisions on target environment.
 case "${host}" in
@ -74203,6 +74214,9 @@ $as_echo "#define HAVE_LINUX_FUTEX 1" >>confdefs.h
 fi


+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>.


 inttype_headers=`echo inttypes.h sys/inttypes.h  | sed -e 's/,/ /g'`
@ -74604,6 +74618,7 @@ ac_config_commands="$ac_config_commands include/gstdint.h"



+fi


  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GNU c++filt" >&5
--- 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)
--- a/libstdc++-v3/doc/Makefile.in
+++ b/libstdc++-v3/doc/Makefile.in
@ -199,6 +199,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/include/Makefile.in
+++ b/libstdc++-v3/include/Makefile.in
@ -199,6 +199,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- 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 = \
--- a/libstdc++-v3/libsupc++/Makefile.in
+++ b/libstdc++-v3/libsupc++/Makefile.in
@ -308,6 +308,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
@ -579,7 +580,7 @@ atomicity_file = ${glibcxx_srcdir}/$(ATOMICITY_SRCDIR)/atomicity.h
 # 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 = \
--- a/libstdc++-v3/po/Makefile.in
+++ b/libstdc++-v3/po/Makefile.in
@ -199,6 +199,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/python/Makefile.in
+++ b/libstdc++-v3/python/Makefile.in
@ -229,6 +229,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/src/Makefile.in
+++ b/libstdc++-v3/src/Makefile.in
@ -298,6 +298,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/src/c++11/Makefile.in
+++ b/libstdc++-v3/src/c++11/Makefile.in
@ -265,6 +265,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/src/c++17/Makefile.in
+++ b/libstdc++-v3/src/c++17/Makefile.in
@ -245,6 +245,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/src/c++20/Makefile.in
+++ b/libstdc++-v3/src/c++20/Makefile.in
@ -240,6 +240,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/src/c++98/Makefile.in
+++ b/libstdc++-v3/src/c++98/Makefile.in
@ -261,6 +261,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/src/filesystem/Makefile.in
+++ b/libstdc++-v3/src/filesystem/Makefile.in
@ -269,6 +269,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@
--- a/libstdc++-v3/testsuite/Makefile.in
+++ b/libstdc++-v3/testsuite/Makefile.in
@ -199,6 +199,7 @@ EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
 EXTRA_CXX_FLAGS = @EXTRA_CXX_FLAGS@
 FGREP = @FGREP@
+FREESTANDING_FLAGS = @FREESTANDING_FLAGS@
 GLIBCXX_INCLUDES = @GLIBCXX_INCLUDES@
 GLIBCXX_LIBS = @GLIBCXX_LIBS@
 GREP = @GREP@