A related annoyance is that when you write a for-loop in a Makefile, every iteration gets run even if one of them fails, due to how the shell calculates exit co

A related annoyance is that when you write a for-loop in a Makefile, every iteration gets run even if one of them fails, due to how the shell calculates exit codes of for-loops. So most of the time you should do "set -e; for XXX". Otherwise your Makefile loops will "succeed" incorrectly.