Bug: https://bugs.gentoo.org/967045

--- a/Makefile.PL
+++ b/Makefile.PL
@@ -209,7 +209,7 @@
 sub CheckExternalDependencies {
   my @dependencies = @_;
   for my $program (@dependencies) {
-    if (system("which $program > /dev/null") != 0) {
+    if (system("command -v $program > /dev/null") != 0) {
       warn "W: Required test dependency not found: $program\n";
     }
   }