diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index b977a802549a..aafc29d31734 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,6 +1,7 @@
 2001-08-23  David Edelsohn  <edelsohn@gnu.org>
 
 	* config/os/gnu-linux/bits/os_defines.h: Correct __s390__ definitions.
+	Set __powerpc__ long double definition based on __LONG_DOUBLE_128__.
 
 2001-08-23  Jason Merrill  <jason_merrill@redhat.com>
 
diff --git a/libstdc++-v3/config/os/gnu-linux/bits/os_defines.h b/libstdc++-v3/config/os/gnu-linux/bits/os_defines.h
index 474238cebb88..2b4375e81eb1 100644
--- a/libstdc++-v3/config/os/gnu-linux/bits/os_defines.h
+++ b/libstdc++-v3/config/os/gnu-linux/bits/os_defines.h
@@ -71,7 +71,7 @@ typedef __loff_t __off64_t;
 #define __glibcpp_long_bits 64
 #endif
 
-#if defined (__alpha__) || defined (__powerpc64__) || defined (__s390__)
+#if defined (__alpha__) || (defined (__powerpc__) && !defined (__LONG_DOUBLE_128__)) || defined (__s390__)
 #define __glibcpp_long_double_bits 64
 #endif