diff --git a/configure1.in b/configure1.in
index 6db9e2eb152..48f908bc43f 100755
--- a/configure1.in
+++ b/configure1.in
@@ -640,6 +640,7 @@ case "${configuration}" in
       *-xenix* )		opsys=xenix ;;
       *-linux* )		opsys=linux ;;
       *-sco3.2v4* )		opsys=sco4 ;;
+      *-bsd386* )		opsys=bsd386 ;;
       ## Otherwise, we'll fall through to the generic opsys code at the bottom.
     esac
   ;;
@@ -843,6 +844,7 @@ case "${configuration}" in
       *-bsd4.1 ) 					opsys=bsd4-1 ;;
       *-bsd4.2 | *-ultrix[0-3].* | *-ultrix4.0 )	opsys=bsd4-2 ;;
       *-bsd4.3 | *-ultrix* ) 				opsys=bsd4-3 ;;
+      *-bsd386 )					opsys=bsd386 ;;
       *-sysv[01]* | *-sysvr[01]* ) 			opsys=usg5-0 ;;
       *-sysv2* | *-sysvr2* )				opsys=usg5-2 ;;
       *-vms* ) 						opsys=vms ;;
@@ -873,7 +875,7 @@ esac
 ### operating system is; if you know what operating systems a machine
 ### runs, it's cleaner to make it explicit in the case statement
 ### above.
-if [ ! "${opsys}" ]; then
+if [ x"${opsys}" = x ]; then
   case "${configuration}" in
     *-bsd4.[01] )	opsys=bsd4-1 ;;
     *-bsd4.2 )		opsys=bsd4-2 ;;
@@ -1098,7 +1100,7 @@ if [ "${system_malloc}" = "yes" ]; then
   (The GNU allocators don't work with this system configuration.)"
 fi
 
-if [ ! "${REL_ALLOC}" ]; then
+if [ x"${REL_ALLOC}" = x ]; then
   REL_ALLOC=${GNU_MALLOC}
 fi
 
@@ -1108,7 +1110,7 @@ LISP_FLOAT_TYPE=yes
 #### Find out which version of Emacs this is.
 version=`grep 'defconst[	 ]*emacs-version' ${srcdir}/lisp/version.el \
 	 | sed -e 's/^.*"\([0-9][0-9]*\.[0-9][0-9]*\)\..*$/\1/'`
-if [ ! "${version}" ]; then
+if [ x"${version}" = x ]; then
   echo "${progname}: can't find current emacs version in
 	\`${srcdir}/lisp/version.el'." >&2
   exit 1