diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index fc6336cef5..3a6f452b2b 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2013-11-18  Tom Tromey  <tromey@redhat.com>
+
+	* config.in: Rebuild.
+	* configure: Rebuild.
+	* configure.ac: Don't check for stddef.h.
+	* defs.h: Unconditionally include stddef.h.  Remove duplicate
+	inclusion.
+
 2013-11-18  Tom Tromey  <tromey@redhat.com>
 
 	* common/common.m4 (GDB_AC_COMMON): Don't use AC_HEADER_DIRENT.
diff --git a/gdb/config.in b/gdb/config.in
index 4e3f6de5d0..802127ff93 100644
--- a/gdb/config.in
+++ b/gdb/config.in
@@ -378,9 +378,6 @@
 /* Define to 1 if the system has the type `socklen_t'. */
 #undef HAVE_SOCKLEN_T
 
-/* Define to 1 if you have the <stddef.h> header file. */
-#undef HAVE_STDDEF_H
-
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 
diff --git a/gdb/configure b/gdb/configure
index b1a4d48a0b..1d1a4867db 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -8756,7 +8756,7 @@ fi
 
 # elf_hp.h is for HP/UX 64-bit shared library support.
 for ac_header in nlist.h machine/reg.h poll.h sys/poll.h proc_service.h \
-                  thread_db.h stddef.h \
+                  thread_db.h \
 		  stdlib.h sys/fault.h \
 		  sys/file.h sys/filio.h sys/ioctl.h sys/param.h \
 		  sys/resource.h sys/procfs.h sys/ptrace.h ptrace.h \
diff --git a/gdb/configure.ac b/gdb/configure.ac
index 6025e8938e..d6b75d61f1 100644
--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -1075,7 +1075,7 @@ fi
 AC_HEADER_STDC
 # elf_hp.h is for HP/UX 64-bit shared library support.
 AC_CHECK_HEADERS([nlist.h machine/reg.h poll.h sys/poll.h proc_service.h \
-                  thread_db.h stddef.h \
+                  thread_db.h \
 		  stdlib.h sys/fault.h \
 		  sys/file.h sys/filio.h sys/ioctl.h sys/param.h \
 		  sys/resource.h sys/procfs.h sys/ptrace.h ptrace.h \
diff --git a/gdb/defs.h b/gdb/defs.h
index b1caaadeaf..bb93742522 100644
--- a/gdb/defs.h
+++ b/gdb/defs.h
@@ -48,9 +48,7 @@
    included, so it's ok to blank out gstdint.h.  */
 #define GCC_GENERATED_STDINT_H 1
 
-#ifdef HAVE_STDDEF_H
 #include <stddef.h>
-#endif
 
 #include <unistd.h>
 
@@ -606,10 +604,6 @@ enum gdb_osabi
 
 /* From other system libraries */
 
-#ifdef HAVE_STDDEF_H
-#include <stddef.h>
-#endif
-
 #ifdef HAVE_STDLIB_H
 #include <stdlib.h>
 #endif