Friday 29 November 2013

Makefile mash

The dumbest thing so far seen in a makefile:

ECHO      = `which echo`

Apart from the apparent fact that the writer assumes that the external command which is on the path but echo might not be (hint: they don't want to use the built-in echo for whatever reason), the main error is that everywhere $(ECHO) is used it will be replaced with `which echo`

The author probably intends

 ECHO      := $(shell which echo)

which will define ECHO to be something like /bin/echo which is what they intended.

Note the := otherwise which echo would be evaluated each time $(ECHO) is used.


2 comments:

  1. You posted a BOM reading chart, verse by verse back in Sept 2011. I wondered if there is any way I could get a copy of it????

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  2. Yes, email me: sam@liddicott.com

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