diff --git a/regress/test-exec.sh b/regress/test-exec.sh
index ed235cfaf..f09fe0ec4 100644
--- a/regress/test-exec.sh
+++ b/regress/test-exec.sh
@@ -164,7 +164,7 @@ if [ "x$USE_VALGRIND" != "x" ]; then
 
 	if [ x"$VG_SKIP" = "x" ]; then
 		VG_LEAK="--leak-check=no"
-		if [ x"$VALGRIND_CHECK_LEAKS" = "x" ]; then
+		if [ x"$VALGRIND_CHECK_LEAKS" != "x" ]; then
 			VG_LEAK="--leak-check=full"
 		fi
 		VG_IGNORE="/bin/*,/sbin/*,/usr/*,/var/*"
diff --git a/regress/valgrind-unit.sh b/regress/valgrind-unit.sh
index c353c2cbc..d1c110008 100755
--- a/regress/valgrind-unit.sh
+++ b/regress/valgrind-unit.sh
@@ -9,7 +9,7 @@ test "x$OBJ" = "x" && OBJ=$PWD
 # This mostly replicates the logic in test-exec.sh for running the
 # regress tests under valgrind.
 VG_LEAK="--leak-check=no"
-if [ x"$VALGRIND_CHECK_LEAKS" = "x" ]; then
+if [ x"$VALGRIND_CHECK_LEAKS" != "x" ]; then
 	VG_LEAK="--leak-check=full"
 fi
 VG_TEST=`basename $UNIT_BINARY`