diff --git a/pkgs/stdenv/generic/setup.sh b/pkgs/stdenv/generic/setup.sh
index 14c64e8020d..d3d2d250e50 100644
--- a/pkgs/stdenv/generic/setup.sh
+++ b/pkgs/stdenv/generic/setup.sh
@@ -198,6 +198,10 @@ findInputs() {
 
     eval $var="'${!var} $pkg '"
 
+    if [ -f $pkg ]; then
+        source $pkg
+    fi
+
     if [ -f $pkg/nix-support/setup-hook ]; then
         source $pkg/nix-support/setup-hook
     fi