diff --git a/configure b/configure
index ff3a59b6b..4c8476502 100755
--- a/configure
+++ b/configure
@@ -3077,7 +3077,7 @@ if test -z "$CFLAGS"; then :
 fi
 case "$host_os" in
 	linux*)
-		CLDFLAGS="${CLDFLAGS:"$LDFLAGS"} -Wl,--version-script,.export.sym"
+		CLDFLAGS="${CLDFLAGS-"$LDFLAGS"} -Wl,--version-script,.export.sym"
 		# equivalent to -rdynamic
 		ELDFLAGS="-Wl,--export-dynamic"
 		# FIXME Generate list and use --dynamic-list=.dlopen.sym
@@ -3098,7 +3098,7 @@ case "$host_os" in
 		;;
 	darwin*)
 		CFLAGS="$CFLAGS -no-cpp-precomp -fno-common"
-		CLDFLAGS="${CLDFLAGS:"$LDFLAGS"}"
+		CLDFLAGS="${CLDFLAGS-"$LDFLAGS"}"
 		ELDFLAGS=
 		CLDWHOLEARCHIVE="-all_load"
 		CLDNOWHOLEARCHIVE=
@@ -3111,7 +3111,7 @@ case "$host_os" in
 		BLKDEACTIVATE=no
 		;;
 	*)
-		CLDFLAGS="${CLDFLAGS:"$LDFLAGS"}"
+		CLDFLAGS="${CLDFLAGS-"$LDFLAGS"}"
 		;;
 esac
 
diff --git a/configure.ac b/configure.ac
index 5da694631..830edb8da 100644
--- a/configure.ac
+++ b/configure.ac
@@ -30,7 +30,7 @@ AC_CANONICAL_TARGET([])
 AS_IF([test -z "$CFLAGS"], [COPTIMISE_FLAG="-O2"])
 case "$host_os" in
 	linux*)
-		CLDFLAGS="${CLDFLAGS:"$LDFLAGS"} -Wl,--version-script,.export.sym"
+		CLDFLAGS="${CLDFLAGS-"$LDFLAGS"} -Wl,--version-script,.export.sym"
 		# equivalent to -rdynamic
 		ELDFLAGS="-Wl,--export-dynamic"
 		# FIXME Generate list and use --dynamic-list=.dlopen.sym
@@ -51,7 +51,7 @@ case "$host_os" in
 		;;
 	darwin*)
 		CFLAGS="$CFLAGS -no-cpp-precomp -fno-common"
-		CLDFLAGS="${CLDFLAGS:"$LDFLAGS"}"
+		CLDFLAGS="${CLDFLAGS-"$LDFLAGS"}"
 		ELDFLAGS=
 		CLDWHOLEARCHIVE="-all_load"
 		CLDNOWHOLEARCHIVE=
@@ -64,7 +64,7 @@ case "$host_os" in
 		BLKDEACTIVATE=no
 		;;
 	*)
-		CLDFLAGS="${CLDFLAGS:"$LDFLAGS"}"
+		CLDFLAGS="${CLDFLAGS-"$LDFLAGS"}"
 		;;
 esac