Problems setting PATH in Makefile

Question

I'm new to make and Makefiles, but I'm trying to create one for my next project and I'm running into PATH issues. I keep getting the error: "No such file or directory"

I've created a simple target called test that runs all my tests using mocha.

Mocha is installed as a local node module, so its executable can be found at ./node_modules/.bin/mocha. I'm altering my PATH as described in this make tutorial so I can refer to it as mocha instead of typing the full path, but something doesn't seem to be working.

Here's what I have so far:

export PATH := node_modules/.bin:$(PATH)

test:
    which mocha
    mocha

.PHONY: test

When I run make test I get the following output:

which mocha
node_modules/.bin/mocha
mocha
make: mocha: No such file or directory
make: *** [test] Error 1

As you can see from the output, which mocha is correctly printing the path to the mocha executable, but when I simply run mocha, it can't find it.

What am I doing wrong? Is there bigger picture about variable scope or persistence in Makefiles that I'm missing?

P.S. If it's important, I'm using a Mac and the version of make that comes with the XCode developer tools. This is what I get when I run make -v

GNU Make 3.81
Copyright (C) 2006  Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.

This program built for i386-apple-darwin11.3.0

Answer 1

In OSX you also need to also set SHELL:

PATH  := node_modules/.bin:$(PATH)
SHELL := /bin/bash

Answer 2

I can't reproduce your results (using GNU make 3.81 on a GNU/Linux system). It appears that there may be some difference in either the way the Apple system works, or that Apple has made some kind of patch to the GNU make version they ship that is causing this problem.

GNU make has two ways of running recipes: the normal way, where it invokes a shell and passes the recipe to the shell to be run, and the "fast path", where, if make sees that the command is "simple enough" (that is if it contains no shell special characters), it will chop up the command into words and directly execute the command without invoking the shell. The latter is much faster, but since it's being invoked directly it inherits the PATH setting from GNU make itself not from the shell.

It appears that for some reason the version of GNU make shipped by Apple is not working properly in that it's not setting the environment correctly for commands which are run directly by GNU make, via the "fast path".

I have a very vague recollection of something like this being discussed on the GNU make mailing lists, but after spending some time searching I wasn't able to come up with anything.

You can "fix" this problem by forcing your command to use the slow path, by introducing some shell special characters (globbing, ;, pipes, etc.). Or you can use a fully-qualified path to the program.

Or, you can go get the source code for GNU make and build it yourself; if this difference is a result of a "fix" by Apple that should make it work better. Or install GNU make from homebrew or ports, which will also get you a newer version with more features, I expect.