diff --git a/extra/libffi/build b/extra/libffi/build
index ed40bd99..b8fbbe0d 100755
--- a/extra/libffi/build
+++ b/extra/libffi/build
@@ -13,5 +13,5 @@ mv    "$1/usr/lib/libffi-3.2.1/include/" "$1/usr"
 rmdir "$1/usr/lib/libffi-3.2.1"
 
 # Fix location inside pkgconfig file.
-sed -i -e '/^includedir=/{s,=.*,=/usr/include,g}' \
+sed -i '/^includedir=/{s,=.*,=/usr/include,g}' \
     "$1/usr/lib/pkgconfig/libffi.pc"