diff --git a/gkbuilds/mdadm.gkbuild b/gkbuilds/mdadm.gkbuild
index b43f753..e8060e5 100644
--- a/gkbuilds/mdadm.gkbuild
+++ b/gkbuilds/mdadm.gkbuild
@@ -16,6 +16,9 @@ src_prepare() {
 }
 
 src_compile() {
+	# bug 907082
+	append-cppflags -D_LARGEFILE64_SOURCE
+
 	gkmake V=1 mdadm mdmon
 }