[Bug libstdc++/122322] [14/15/16 regression] libstdc++-v3 autoreconf broken since r16-4443-g651bf5126da124

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122322

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I think we want this, and then autoreconf:

--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -399,10 +399,8 @@ dnl # rather than hardcoding that information.
         AC_DEFINE(HAVE_ALIGNED_ALLOC)
         AC_DEFINE(HAVE_AT_QUICK_EXIT)
         AC_DEFINE(HAVE_LINK)
-        AC_DEFINE(HAVE_SYS_IOCT4YL_H)
         AC_DEFINE(HAVE_SYS_STAT_H)
         AC_DEFINE(HAVE_SYS_TYPES_H)
-        AC_DEFINE(HAVE_S_ISREG)
         AC_DEFINE(HAVE_QUICK_EXIT)
         AC_DEFINE(HAVE_READLINK)
         AC_DEFINE(HAVE_SETENV)
@@ -410,9 +408,6 @@ dnl # rather than hardcoding that information.
         AC_DEFINE(HAVE_SOCKATMARK)
         AC_DEFINE(HAVE_STRERROR_L)
         AC_DEFINE(HAVE_SYMLINK)
-        AC_DEFINE(HAVE_SYS_IOCT4YL_H)
-        AC_DEFINE(HAVE_SYS_STAT_H)
-        AC_DEFINE(HAVE_SYS_TYPES_H)
         AC_DEFINE(HAVE_S_ISREG)
         AC_DEFINE(HAVE_TRUNCATE)
         AC_DEFINE(HAVE_UNISTD_H)
@@ -423,11 +418,6 @@ dnl # rather than hardcoding that information.
         AC_DEFINE(_GLIBCXX_USE_CHDIR)
         AC_DEFINE(_GLIBCXX_USE_GETCWD)
         AC_DEFINE(_GLIBCXX_USE_UTIME)
-        AC_DEFINE(_GLIBCXX_USE_LINK)
-        AC_DEFINE(_GLIBCXX_USE_READLINK)
-        AC_DEFINE(_GLIBCXX_USE_SYMLINK)
-        AC_DEFINE(_GLIBCXX_USE_TRUNCATE)
-        AC_DEFINE(_GLIBCXX_USE_FDOPENDIR)
         AC_DEFINE(HAVE_USLEEP)

         # These functions are defined in librtemscpu.  We don't use