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Say in ~/prj/abc/abcsim/abctsim/abcxyz/Makefile there is a line below.

TOOLCHAIN_DIR   := $(PWD)/../../../prj1/tools/gcc_tools

If I'm in directory ~/test, and if I run make -C ~/prj/abc/abcsim/abctsim/abcxyz, this doesn't work because the $(PWD) variable is set to ~/test, not ~/prj/abc/abcsim/abctsim/abcxyz. How can I get the directory path where the Makefile exists?
In bash there's something for this : How can I get the source directory of a Bash script from within the script itself?

Renaud Pacalet
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Chan Kim
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  • Just to be entirely clear, make has no special handling at all for a variable `PWD`. As far as make is concerned, `PWD` is just another variable that it inherits from the shell, like `PATH` and `USER` etc. So, the value of `PWD` inside your makefile is whatever value your _shell_ passed in, which is the working directory of your shell before you invoked make. As pointed out below, `CURDIR` is a _make_ variable that it will set to the working directory make is running in after `-C` is processed. – MadScientist May 19 '21 at 13:49

1 Answers1

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If you really use make -C (not make -f) and your Makefile is not included in another, you can simply use the CURDIR variable. GNU make sets it to the absolute path of the current directory when it starts, "after it has processed any -C options". So, in your case it should do exactly what you want.

Else, if you sometimes use make -f or if you have included Makefiles, you can put this as the first line of any of your Makefiles (or, at least, before any include statement):

HERE := $(dir $(lastword $(MAKEFILE_LIST)))

and then use $(HERE) to refer to this Makefile's directory. See the GNU make manual for the details.

Note: I was almost sure this question would be a duplicate. Surprisingly I searched SO for a clear answer and found only old answers that first suggest shell calls before using make built-ins or wrong answers (using firstword instead of lastword, for instance).

Renaud Pacalet
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