What does -include mean in an Android.mk file?

Question

I am a newbie to Android makefiles. While reading this file I see a "-include" statement.

What does this actually mean to the build system?

Answer 1

The include simply means that another makefile should be included. The - means that if the file to include doesn't exist it will simply be ignored:

We can also put a minus sign - in front of include (with no space in-between) to ignore filenames that do not exist. For example:

-include makefile1 makefile2 makefile3

If makefile2 does not exist, then make will skip it, and no error will occur. In general, inserting a minus sign in front of any command tells make to ignore errors that might occur during the execution of that command.

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