libstdc++: Add C++ runtime support for new 128-bit long double format

This adds support for the new __ieee128 long double format on powerpc64le targets. Most of the complexity comes from wanting a single libstdc++.so library that contains the symbols needed by code compiled with both -mabi=ibmlongdouble and -mabi=ieeelongdouble (and not forgetting -mlong-double-64 as well!) In a few places this just requires an extra overload, for example std::from_chars has to be overloaded for both forms of long double. That can be done in a single translation unit that defines overloads for 'long double' and also '__ieee128', so that user code including <charconv> will be able to link to a definition for either type of long double. Those are the easy cases. The difficult parts are (as for the std::string ABI transition) the I/O and locale facets. In order to be able to write either form of long double to an ostream such as std::cout we need the locale to contain a std::num_put facet that can handle both forms. The same approach is taken as was already done for supporting 64-bit long double and 128-bit long double: adding extra overloads of do_put to the facet class. On targets where the new long double code is enabled, the facets that are registered in the locale at program startup have additional overloads so that they can work with any long double type. Where this fails to work is if user code installs its own facet, which will probably not have the additional overloads and so will only be able to output one or the other type. In practice the number of users expecting to be able to use their own locale facets in code using a mix of -mabi=ibmlongdouble and -mabi=ieeelongdouble is probably close to zero. libstdc++-v3/ChangeLog: * Makefile.in: Regenerate. * config.h.in: Regenerate. * config/abi/pre/gnu.ver: Make patterns less greedy. * config/os/gnu-linux/ldbl-ieee128-extra.ver: New file with patterns for IEEE128 long double symbols. * configure: Regenerate. * configure.ac: Enable alternative 128-bit long double format on powerpc64*-*-linux*. * doc/Makefile.in: Regenerate. * fragment.am: Regenerate. * include/Makefile.am: Set _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT. * include/Makefile.in: Regenerate. * include/bits/c++config: Define inline namespace for new long double symbols. Don't define _GLIBCXX_USE_FLOAT128 when it's the same type as long double. * include/bits/locale_classes.h [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT] (locale::_Impl::_M_init_extra_ldbl128): Declare new member function. * include/bits/locale_facets.h (_GLIBCXX_NUM_FACETS): Simplify by only counting narrow character facets. (_GLIBCXX_NUM_CXX11_FACETS): Likewise. (_GLIBCXX_NUM_LBDL_ALT128_FACETS): New. [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT] (num_get::__do_get): Define vtable placeholder for __ibm128 long double type. [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT && __LONG_DOUBLE_IEEE128__] (num_get::__do_get): Declare vtable placeholder for __ibm128 long double type. [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT && __LONG_DOUBLE_IEEE128__] (num_put::__do_put): Likewise. * include/bits/locale_facets.tcc [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT && __LONG_DOUBLE_IEEE128__] (num_get::__do_get, num_put::__do_put): Define. * include/bits/locale_facets_nonio.h [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT && __LONG_DOUBLE_IEEE128__] (money_get::__do_get): Declare vtable placeholder for __ibm128 long double type. [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT && __LONG_DOUBLE_IEEE128__] (money_put::__do_put): Likewise. * include/bits/locale_facets_nonio.tcc [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT && __LONG_DOUBLE_IEEE128__] (money_get::__do_get, money_put::__do_put): Define. * include/ext/numeric_traits.h [_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT] (__numeric_traits<__ibm128>, __numeric_traits<__ieee128>): Define. * libsupc++/Makefile.in: Regenerate. * po/Makefile.in: Regenerate. * python/Makefile.in: Regenerate. * src/Makefile.am: Add compatibility-ldbl-alt128.cc and compatibility-ldbl-alt128-cxx11.cc sources and recipes for objects. * src/Makefile.in: Regenerate. * src/c++11/Makefile.in: Regenerate. * src/c++11/compatibility-ldbl-alt128-cxx11.cc: New file defining symbols using the old 128-bit long double format, for the cxx11 ABI. * src/c++11/compatibility-ldbl-alt128.cc: Likewise, for the gcc4-compatible ABI. * src/c++11/compatibility-ldbl-facets-aliases.h: New header for long double compat aliases. * src/c++11/cow-locale_init.cc: Add comment. * src/c++11/cxx11-locale-inst.cc: Define C and C_is_char unconditionally. * src/c++11/cxx11-wlocale-inst.cc: Add sanity check. Include locale-inst.cc directly, not via cxx11-locale-inst.cc. * src/c++11/locale-inst-monetary.h: New header for monetary category instantiations. * src/c++11/locale-inst-numeric.h: New header for numeric category instantiations. * src/c++11/locale-inst.cc: Include new headers for monetary, numeric, and long double definitions. * src/c++11/wlocale-inst.cc: Remove long double compat aliases that are defined in new header now. * src/c++17/Makefile.am: Use -mabi=ibmlongdouble for floating_from_chars.cc. * src/c++17/Makefile.in: Regenerate. * src/c++17/floating_from_chars.cc (from_chars_impl): Add if-constexpr branch for __ieee128. (from_chars): Overload for __ieee128. * src/c++20/Makefile.in: Regenerate. * src/c++98/Makefile.in: Regenerate. * src/c++98/locale_init.cc (num_facets): Adjust calculation. (locale::_Impl::_Impl(size_t)): Call _M_init_extra_ldbl128. * src/c++98/localename.cc (num_facets): Adjust calculation. (locale::_Impl::_Impl(const char*, size_t)): Call _M_init_extra_ldbl128. * src/filesystem/Makefile.in: Regenerate. * testsuite/Makefile.in: Regenerate. * testsuite/util/testsuite_abi.cc: Add new symbol versions. Allow new symbols to be added to GLIBCXX_IEEE128_3.4.29 and CXXABI_IEEE128_1.3.13 too. * testsuite/26_numerics/complex/abi_tag.cc: Add u9__ieee128 to regex matching expected symbols.
gcc-mirror · Dec 16, 2020 · 7c1e7ee · 7c1e7ee
1 parent f4ae1f2
commit 7c1e7ee
Show file tree

Hide file tree

Showing 44 changed files with 1,380 additions and 311 deletions.
diff --git a/libstdc++-v3/Makefile.in b/libstdc++-v3/Makefile.in
@@ -257,6 +257,8 @@ LIBS = @LIBS@
 LIBTOOL = @LIBTOOL@
 LIPO = @LIPO@
 LN_S = @LN_S@
+LONG_DOUBLE_128_FLAGS = @LONG_DOUBLE_128_FLAGS@
+LONG_DOUBLE_ALT128_COMPAT_FLAGS = @LONG_DOUBLE_ALT128_COMPAT_FLAGS@
 LONG_DOUBLE_COMPAT_FLAGS = @LONG_DOUBLE_COMPAT_FLAGS@
 LTLIBICONV = @LTLIBICONV@
 LTLIBOBJS = @LTLIBOBJS@
@@ -396,11 +398,13 @@ toolexeclibdir = $(glibcxx_toolexeclibdir)
 @ENABLE_WERROR_TRUE@WERROR_FLAG = -Werror
 @ENABLE_EXTERN_TEMPLATE_FALSE@XTEMPLATE_FLAGS = 
 @ENABLE_EXTERN_TEMPLATE_TRUE@XTEMPLATE_FLAGS = -fno-implicit-templates
+@GLIBCXX_LDBL_ALT128_COMPAT_FALSE@LDBL_128_FLAGS = 
+@GLIBCXX_LDBL_ALT128_COMPAT_TRUE@LDBL_128_FLAGS = $(LONG_DOUBLE_128_FLAGS)
 
 # These bits are all figured out from configure.  Look in acinclude.m4
 # or configure.ac to see how they are set.  See GLIBCXX_EXPORT_FLAGS.
 CONFIG_CXXFLAGS = \
-	$(SECTION_FLAGS) $(HWCAP_CFLAGS) -frandom-seed=$@
+	$(SECTION_FLAGS) $(HWCAP_CFLAGS) -frandom-seed=$@ $(LDBL_128_FLAGS)
 
 WARN_CXXFLAGS = \
 	$(WARN_FLAGS) $(WERROR_FLAG) -fdiagnostics-show-location=once 

diff --git a/libstdc++-v3/config.h.in b/libstdc++-v3/config.h.in
@@ -882,6 +882,10 @@
 /* Define to 1 if a full hosted library is built, or 0 if freestanding. */
 #undef _GLIBCXX_HOSTED
 
+/* Define if compatibility should be provided for alternative 128-bit long
+   double formats. */
+#undef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT
+
 /* Define if compatibility should be provided for -mlong-double-64. */
 #undef _GLIBCXX_LONG_DOUBLE_COMPAT
 

diff --git a/libstdc++-v3/config/abi/pre/gnu.ver b/libstdc++-v3/config/abi/pre/gnu.ver
@@ -682,7 +682,7 @@ GLIBCXX_3.4 {
     _ZNSt12__basic_fileIcED*;
 
     # std::__convert_to_v
-    _ZSt14__convert_to_vI[^g]*;
+    _ZSt14__convert_to_vI[^gU]*;
 
     # __gnu_cxx::stdio_sync_filebuf
     _ZTVN9__gnu_cxx18stdio_sync_filebufI[cw]St11char_traitsI[cw]EEE;
@@ -931,7 +931,7 @@ GLIBCXX_3.4 {
     _ZGVNSt8time_putI[cw]*;
     _ZGVNSt9money_getI[cw]*;
     _ZGVNSt9money_putI[cw]*;
-    _ZGVNSt1[^07]*;
+    _ZGVNSt1[^079]*;
     _ZGVNSt10moneypunctI[cw]Lb[01]*;
 
     # exception constructors taking std::string

diff --git a/libstdc++-v3/config/os/gnu-linux/ldbl-ieee128-extra.ver b/libstdc++-v3/config/os/gnu-linux/ldbl-ieee128-extra.ver
@@ -0,0 +1,53 @@
+# Appended to version file.
+
+GLIBCXX_IEEE128_3.4.29 {
+
+  *__gnu_cxx_ieee128*;
+
+  _ZNSt14numeric_limitsIu9__ieee128E*;
+  _ZNSirsERu9__ieee128;
+  _ZNSolsEu9__ieee128;
+  _ZNSt13basic_istreamIwSt11char_traitsIwEErsERu9__ieee128;
+  _ZNSt13basic_ostreamIwSt11char_traitsIwEElsEu9__ieee128;
+  _ZSt14__convert_to_vIu9__ieee128EvPKcRT_RSt12_Ios_IostateRKP*;
+  _ZStlsIu9__ieee128[cw]St11char_traitsI[cw]EERSt13basic_ostreamIT0_T1_ES6_RKSt7complexIT_E;
+  _ZStrsIu9__ieee128[cw]St11char_traitsI[cw]EERSt13basic_istreamIT0_T1_ES6_RSt7complexIT_E;
+
+  _ZNSi10_M_extractIu9__ieee128EERSiRT_;
+  _ZNSt13basic_istreamIwSt11char_traitsIwEE10_M_extractIu9__ieee128EERS2_RT_;
+  _ZNSo9_M_insertIu9__ieee128EERSoT_;
+  _ZNSt13basic_ostreamIwSt11char_traitsIwEE9_M_insertIu9__ieee128EERS2_T_;
+
+  _ZNKSt3tr14hashIu9__ieee128EclEu9__ieee128;
+  _ZNKSt4hashIu9__ieee128EclEu9__ieee128;
+
+  _ZNKSt19__gnu_cxx11_ieee1289money_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE6do_getES4_S4_bRSt8ios_baseRSt12_Ios_IostateRNSt7__cxx1112basic_stringIcS3_SaIcEEE;
+  _ZNKSt19__gnu_cxx11_ieee1289money_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE6do_getES4_S4_bRSt8ios_baseRSt12_Ios_IostateRu9__ieee128;
+  _ZNKSt19__gnu_cxx11_ieee1289money_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE8__do_getES4_S4_bRSt8ios_baseRSt12_Ios_IostateRd;
+  _ZNKSt19__gnu_cxx11_ieee1289money_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE8__do_getES4_S4_bRSt8ios_baseRSt12_Ios_IostateRg;
+  _ZNKSt19__gnu_cxx11_ieee1289money_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE6do_putES4_bRSt8ios_basecRKNSt7__cxx1112basic_stringIcS3_SaIcEEE;
+  _ZNKSt19__gnu_cxx11_ieee1289money_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE6do_putES4_bRSt8ios_basecu9__ieee128;
+  _ZNKSt19__gnu_cxx11_ieee1289money_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE8__do_putES4_bRSt8ios_basecd;
+  _ZNKSt19__gnu_cxx11_ieee1289money_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE8__do_putES4_bRSt8ios_basecg;
+  _ZSt9has_facetINSt19__gnu_cxx11_ieee1289money_getI[cw]St19istreambuf_iteratorI[cw]St11char_traitsI[cw]EEEEEbRKSt6locale;
+  _ZSt9has_facetINSt19__gnu_cxx11_ieee1289money_putI[cw]St19ostreambuf_iteratorI[cw]St11char_traitsI[cw]EEEEEbRKSt6locale;
+  _ZSt9use_facetINSt19__gnu_cxx11_ieee1289money_getI[cw]St19istreambuf_iteratorI[cw]St11char_traitsI[cw]EEEEERKT_RKSt6locale;
+  _ZSt9use_facetINSt19__gnu_cxx11_ieee1289money_putI[cw]St19ostreambuf_iteratorI[cw]St11char_traitsI[cw]EEEEERKT_RKSt6locale;
+  _ZTINSt19__gnu_cxx11_ieee1289money_getI[cw]St19istreambuf_iteratorI[cw]St11char_traitsI[cw]EEEE;
+  _ZTVNSt19__gnu_cxx11_ieee1289money_getI[cw]St19istreambuf_iteratorI[cw]St11char_traitsI[cw]EEEE;
+  _ZTINSt19__gnu_cxx11_ieee1289money_putI[cw]St19ostreambuf_iteratorI[cw]St11char_traitsI[cw]EEEE;
+  _ZTVNSt19__gnu_cxx11_ieee1289money_putI[cw]St19ostreambuf_iteratorI[cw]St11char_traitsI[cw]EEEE;
+
+  _ZNKSt19__gnu_cxx11_ieee1289money_putI[cw]St19ostreambuf_iteratorI[cw]St11char_traitsI[cw]EEE3putES4_bRSt8ios_base[cw]u9__ieee128;
+
+  _ZSt10from_charsPKcS0_Ru9__ieee128St12chars_format;
+
+} GLIBCXX_3.4.29;
+
+CXXABI_IEEE128_1.3.13 {
+
+  _ZT[IS]u9__ieee128;
+  _ZT[IS]Pu9__ieee128;
+  _ZT[IS]PKu9__ieee128;
+
+} CXXABI_1.3.13;
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
@@ -680,8 +680,12 @@ ENABLE_FILESYSTEM_TS_TRUE
 baseline_subdir_switch
 baseline_dir
 HWCAP_CFLAGS
+GLIBCXX_LDBL_ALT128_COMPAT_FALSE
+GLIBCXX_LDBL_ALT128_COMPAT_TRUE
 GLIBCXX_LDBL_COMPAT_FALSE
 GLIBCXX_LDBL_COMPAT_TRUE
+LONG_DOUBLE_ALT128_COMPAT_FLAGS
+LONG_DOUBLE_128_FLAGS
 LONG_DOUBLE_COMPAT_FLAGS
 ENABLE_CXX11_ABI_FALSE
 ENABLE_CXX11_ABI_TRUE
@@ -12136,7 +12140,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12139 "configure"
+#line 12143 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12242,7 +12246,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12245 "configure"
+#line 12249 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -15934,7 +15938,7 @@ $as_echo "$glibcxx_cv_atomic_long_long" >&6; }
   # Fake what AC_TRY_COMPILE does.
 
     cat > conftest.$ac_ext << EOF
-#line 15937 "configure"
+#line 15941 "configure"
 int main()
 {
   typedef bool atomic_type;
@@ -15969,7 +15973,7 @@ $as_echo "$glibcxx_cv_atomic_bool" >&6; }
     rm -f conftest*
 
     cat > conftest.$ac_ext << EOF
-#line 15972 "configure"
+#line 15976 "configure"
 int main()
 {
   typedef short atomic_type;
@@ -16004,7 +16008,7 @@ $as_echo "$glibcxx_cv_atomic_short" >&6; }
     rm -f conftest*
 
     cat > conftest.$ac_ext << EOF
-#line 16007 "configure"
+#line 16011 "configure"
 int main()
 {
   // NB: _Atomic_word not necessarily int.
@@ -16040,7 +16044,7 @@ $as_echo "$glibcxx_cv_atomic_int" >&6; }
     rm -f conftest*
 
     cat > conftest.$ac_ext << EOF
-#line 16043 "configure"
+#line 16047 "configure"
 int main()
 {
   typedef long long atomic_type;
@@ -16193,7 +16197,7 @@ $as_echo "mutex" >&6; }
   # unnecessary for this test.
 
     cat > conftest.$ac_ext << EOF
-#line 16196 "configure"
+#line 16200 "configure"
 int main()
 {
   _Decimal32 d1;
@@ -16235,7 +16239,7 @@ ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
   # unnecessary for this test.
 
     cat > conftest.$ac_ext << EOF
-#line 16238 "configure"
+#line 16242 "configure"
 template<typename T1, typename T2>
   struct same
   { typedef T2 type; };
@@ -16269,7 +16273,7 @@ $as_echo "$enable_int128" >&6; }
     rm -f conftest*
 
     cat > conftest.$ac_ext << EOF
-#line 16272 "configure"
+#line 16276 "configure"
 template<typename T1, typename T2>
   struct same
   { typedef T2 type; };
@@ -75695,7 +75699,11 @@ $as_echo "${default_libstdcxx_abi}" >&6; }
 
 
 ac_ldbl_compat=no
+ac_ldbl_alt128_compat=no
+ac_ldbl_ieee128_default=no
 LONG_DOUBLE_COMPAT_FLAGS="-mlong-double-64"
+LONG_DOUBLE_128_FLAGS=
+LONG_DOUBLE_ALT128_COMPAT_FLAGS=
 case "$target" in
   powerpc*-*-linux* | \
   sparc*-*-linux* | \
@@ -75729,13 +75737,103 @@ $as_echo "#define _GLIBCXX_LONG_DOUBLE_COMPAT 1" >>confdefs.h
     port_specific_symbol_files="\$(top_srcdir)/config/os/gnu-linux/ldbl-extra.ver"
     case "$target" in
       powerpc*-*-linux*)
-	LONG_DOUBLE_COMPAT_FLAGS="$LONG_DOUBLE_COMPAT_FLAGS -mno-gnu-attribute" ;;
+	LONG_DOUBLE_COMPAT_FLAGS="$LONG_DOUBLE_COMPAT_FLAGS -mno-gnu-attribute"
+        # Check for IEEE128 support in libm:
+        { $as_echo "$as_me:${as_lineno-$LINENO}: checking for __frexpieee128 in -lm" >&5
+$as_echo_n "checking for __frexpieee128 in -lm... " >&6; }
+if ${ac_cv_lib_m___frexpieee128+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lm  $LIBS"
+if test x$gcc_no_link = xyes; then
+  as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5
+fi
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char __frexpieee128 ();
+int
+main ()
+{
+return __frexpieee128 ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_m___frexpieee128=yes
+else
+  ac_cv_lib_m___frexpieee128=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m___frexpieee128" >&5
+$as_echo "$ac_cv_lib_m___frexpieee128" >&6; }
+if test "x$ac_cv_lib_m___frexpieee128" = xyes; then :
+  ac_ldbl_ieee128_in_libc=yes
+else
+  ac_ldbl_ieee128_in_libc=no
+fi
+
+        if test $ac_ldbl_ieee128_in_libc = yes; then
+          # Determine which long double format is the compiler's default:
+          cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+            #ifndef __LONG_DOUBLE_IEEE128__
+            #error compiler defaults to ibm128
+            #endif
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  ac_ldbl_ieee128_default=yes
+else
+  ac_ldbl_ieee128_default=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+          # Library objects should use default long double format.
+          if test "$ac_ldbl_ieee128_default" = yes; then
+            LONG_DOUBLE_128_FLAGS="-mno-gnu-attribute"
+            # Except for the ones that explicitly use these flags:
+            LONG_DOUBLE_ALT128_COMPAT_FLAGS="-mabi=ibmlongdouble -mno-gnu-attribute -Wno-psabi"
+          else
+            LONG_DOUBLE_128_FLAGS="-mno-gnu-attribute"
+            LONG_DOUBLE_ALT128_COMPAT_FLAGS="-mabi=ieeelongdouble -mno-gnu-attribute -Wno-psabi"
+          fi
+
+$as_echo "#define _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT 1" >>confdefs.h
+
+          port_specific_symbol_files="$port_specific_symbol_files \$(top_srcdir)/config/os/gnu-linux/ldbl-ieee128-extra.ver"
+          ac_ldbl_alt128_compat=yes
+        else
+          ac_ldbl_alt128_compat=no
+        fi
+	;;
     esac
   fi
 esac
 
 
 
+
+
+
 # Check if assembler supports disabling hardware capability support.
 
   test -z "$HWCAP_CFLAGS" && HWCAP_CFLAGS=''
@@ -78268,6 +78366,15 @@ else
 fi
 
 
+    if test $ac_ldbl_alt128_compat = yes; then
+  GLIBCXX_LDBL_ALT128_COMPAT_TRUE=
+  GLIBCXX_LDBL_ALT128_COMPAT_FALSE='#'
+else
+  GLIBCXX_LDBL_ALT128_COMPAT_TRUE='#'
+  GLIBCXX_LDBL_ALT128_COMPAT_FALSE=
+fi
+
+
     if test $enable_libstdcxx_filesystem_ts = yes; then
   ENABLE_FILESYSTEM_TS_TRUE=
   ENABLE_FILESYSTEM_TS_FALSE='#'
@@ -78778,6 +78885,10 @@ if test -z "${GLIBCXX_LDBL_COMPAT_TRUE}" && test -z "${GLIBCXX_LDBL_COMPAT_FALSE
   as_fn_error $? "conditional \"GLIBCXX_LDBL_COMPAT\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${GLIBCXX_LDBL_ALT128_COMPAT_TRUE}" && test -z "${GLIBCXX_LDBL_ALT128_COMPAT_FALSE}"; then
+  as_fn_error $? "conditional \"GLIBCXX_LDBL_ALT128_COMPAT\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 if test -z "${ENABLE_FILESYSTEM_TS_TRUE}" && test -z "${ENABLE_FILESYSTEM_TS_FALSE}"; then
   as_fn_error $? "conditional \"ENABLE_FILESYSTEM_TS\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5