diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 8e752bc2c4f..9e7f917460c 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,3 +1,8 @@
+2018-09-25  Tom Tromey  <tom@tromey.com>
+
+	* configure: Rebuild.
+	* configure.ac (WARN_CFLAGS): Don't remove -Wmissing-prototypes.
+
 2018-09-16  Simon Marchi  <simon.marchi@polymtl.ca>
 
 	* Makefile.in (gdbserver$(EXEEXT)): Sort OBS.
diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure
index f5cbbaea78a..43846659fb9 100755
--- a/gdb/gdbserver/configure
+++ b/gdb/gdbserver/configure
@@ -7391,11 +7391,6 @@ ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
-case " $WARN_CFLAGS " in
-*" -Wmissing-prototypes "*)
-  WARN_CFLAGS="$WARN_CFLAGS -Wno-missing-prototypes"
-  ;;
-esac
 
 old_LIBS="$LIBS"
 LIBS="$LIBS -ldl"
diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index 99bc46221ca..fa3ca53efdc 100644
--- a/gdb/gdbserver/configure.ac
+++ b/gdb/gdbserver/configure.ac
@@ -157,12 +157,6 @@ AC_SUBST(ustlibs)
 AC_SUBST(ustinc)
 
 AM_GDB_WARNINGS
-dnl The codebase isn't clean yet with this flag.
-case " $WARN_CFLAGS " in
-*" -Wmissing-prototypes "*)
-  WARN_CFLAGS="$WARN_CFLAGS -Wno-missing-prototypes"
-  ;;
-esac
 
 dnl dladdr is glibc-specific.  It is used by thread-db.c but only for
 dnl debugging messages.  It lives in -ldl which is handled below so we don't