How does "make" app know default target to build if no target is specified?

Most Linux apps are compiled with:

make
make install clean

As I understand it, the make command takes names of build targets as arguments. So for example install is usually a target that copies some files to standard locations, and clean is a target that removes temporary files.

But what target will make build if no arguments are specified (e.g. the first command in my example)?

Solution 1:

By default, it begins by processing the first target that does not begin with a . aka the default goal; to do that, it may have to process other targets - specifically, ones the first target depends on.

The GNU Make Manual covers all this stuff, and is a surprisingly easy and informative read.

Solution 2:

To save others a few seconds, and to save them from having to read the manual, here's the short answer. Add this to the top of your make file:

.DEFAULT_GOAL := mytarget

mytarget will now be the target that is run if "make" is executed and no target is specified.

If you have an older version of make (<= 3.80), this won't work. If this is the case, then you can do what anon mentions, simply add this to the top of your make file:

.PHONY: default
default: mytarget ;

References: https://www.gnu.org/software/make/manual/html_node/How-Make-Works.html