t / t5100 / patch0015on commit configure: avoid some code repetitions thanks to m4_{push,pop}def (99cccef)
   1---
   2diff --git a/foo b/foo
   3index e69de29..d95f3ad 100644
   4--- a/foo
   5+++ b/foo
   6@@ -0,0 +1 @@
   7+content
   8