diff --git a/corepkgs/fetchurl/fetchurl.sh.in b/corepkgs/fetchurl/fetchurl.sh.in
index dc92c7ee50..7e876a25e2 100644
--- a/corepkgs/fetchurl/fetchurl.sh.in
+++ b/corepkgs/fetchurl/fetchurl.sh.in
@@ -4,7 +4,7 @@ echo "downloading $url into $out..."
 @wget@ "$url" -O "$out" || exit 1
 
 actual=$(@bindir@/nix-hash --flat $out)
-if ! test "$actual" == "$md5"; then
+if test "$actual" != "$md5"; then
     echo "hash is $actual, expected $md5"
     exit 1
 fi