diff --git a/extra/glib/build b/extra/glib/build
index f2bf7860..6c7ea99a 100755
--- a/extra/glib/build
+++ b/extra/glib/build
@@ -1,5 +1,7 @@
 #!/bin/sh -e
 
+export DESTDIR="$1"
+
 # Remove 'libelf' dependency.
 sed -i'' 's/if have_libelf/if not have_libelf/' gio/meson.build
 
@@ -10,7 +12,7 @@ meson \
     . build
 
 ninja -C build
-DESTDIR="$1" ninja -C build install
+ninja -C build install
 
 # Purge gdbus.
 rm -rf "$1/usr/bin/gdbus"