diff --git a/tests/runtests.pl b/tests/runtests.pl
index 2708800318..8e3b58bd68 100755
--- a/tests/runtests.pl
+++ b/tests/runtests.pl
@@ -545,7 +545,7 @@ sub checksystemfeatures {
             $curl =~ s/^(.*)(libcurl.*)/$1/g || die "Failure determining curl binary version";
 
             $libcurl = $2;
-            if($curl =~ /linux|bsd|solaris/) {
+            if($curl =~ /linux|bsd|solaris/i) {
                 # system supports LD_PRELOAD/LD_LIBRARY_PATH; may be disabled later
                 $feature{"ld_preload"} = 1;
             }