diff --git a/.github/test.sh b/.github/test.sh
index f49eee291..ce6118f36 100755
--- a/.github/test.sh
+++ b/.github/test.sh
@@ -7,11 +7,11 @@ cd ivtest
 
 if [ "$OS" = 'Windows_NT' ]; then
   perl update_msys2_report.pl
-  perl vvp_reg.pl $suffix
+  perl vvp_reg.pl -suffix=$suffix
   diff --strip-trailing-cr regression_report-msys2.txt regression_report.txt
 else
-  perl vvp_reg.pl $suffix
+  perl vvp_reg.pl -suffix=$suffix
   diff regression_report-devel.txt regression_report.txt
 fi
 
-perl vpi_reg.pl $suffix
+perl vpi_reg.pl -suffix=$suffix