diff --git a/configure b/configure
index 2176a989f9..10ae152304 100755
--- a/configure
+++ b/configure
@@ -29127,7 +29127,7 @@ fi
 # check for <perl.h>
 if test "$with_perl" = yes; then
   ac_save_CPPFLAGS=$CPPFLAGS
-  CPPFLAGS="-I$perl_archlibexp/CORE $CPPFLAGS"
+  CPPFLAGS="$CPPFLAGS -I$perl_archlibexp/CORE"
   { $as_echo "$as_me:$LINENO: checking for perl.h" >&5
 $as_echo_n "checking for perl.h... " >&6; }
 if test "${ac_cv_header_perl_h+set}" = set; then
diff --git a/configure.in b/configure.in
index 3e72af471f..e2682f3da5 100644
--- a/configure.in
+++ b/configure.in
@@ -1795,7 +1795,7 @@ fi
 # check for <perl.h>
 if test "$with_perl" = yes; then
   ac_save_CPPFLAGS=$CPPFLAGS
-  CPPFLAGS="-I$perl_archlibexp/CORE $CPPFLAGS"
+  CPPFLAGS="$CPPFLAGS -I$perl_archlibexp/CORE"
   AC_CHECK_HEADER(perl.h, [], [AC_MSG_ERROR([header file <perl.h> is required for Perl])],
                   [#include <EXTERN.h>])
   # While we're at it, check that we can link to libperl.