diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index e4175ea3e641c7b99863891b36918a796fd4faa9..1c0a4c130525466bf12fd6892fb624d0b95636de 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -4097,7 +4097,7 @@ AC_DEFUN([GLIBCXX_CHECK_GTHREADS], [
       [ac_have_posix_semaphore=no])
 
   if test $ac_have_posix_semaphore = yes ; then
-    AC_DEFINE(_GLIBCXX_HAVE_POSIX_SEMAPHORE,
+    AC_DEFINE(HAVE_POSIX_SEMAPHORE,
 	      1,
 	      [Define to 1 if POSIX Semaphores with sem_timedwait are available in <semaphore.h>.])
   fi
diff --git a/libstdc++-v3/config.h.in b/libstdc++-v3/config.h.in
index d36ca2620b45888ad35d94adb9d85c72c2394939..37b56b82b0ea35c1ecc697d0c1cc9fb2bc6400f6 100644
--- a/libstdc++-v3/config.h.in
+++ b/libstdc++-v3/config.h.in
@@ -291,6 +291,10 @@
 /* Define to 1 if you have the `posix_memalign' function. */
 #undef HAVE_POSIX_MEMALIGN
 
+/* Define to 1 if POSIX Semaphores with sem_timedwait are available in
+   <semaphore.h>. */
+#undef HAVE_POSIX_SEMAPHORE
+
 /* Define to 1 if you have the `powf' function. */
 #undef HAVE_POWF
 
@@ -818,10 +822,6 @@
 /* Define if gthreads library is available. */
 #undef _GLIBCXX_HAS_GTHREADS
 
-/* Define to 1 if POSIX Semaphores with sem_timedwait are available in
-   <semaphore.h>. */
-#undef _GLIBCXX_HAVE_POSIX_SEMAPHORE
-
 /* Define to 1 if a full hosted library is built, or 0 if freestanding. */
 #undef _GLIBCXX_HOSTED
 
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 13f2e697ed2833feb1a71851ddb5ac42c80305e3..326a279c54f218ee55a62aad28b2ef12009e1bf2 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -75836,7 +75836,7 @@ fi
 
   if test $ac_have_posix_semaphore = yes ; then
 
-$as_echo "#define _GLIBCXX_HAVE_POSIX_SEMAPHORE 1" >>confdefs.h
+$as_echo "#define HAVE_POSIX_SEMAPHORE 1" >>confdefs.h
 
   fi
   { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_have_posix_semaphore" >&5