UNIX for Advanced & Expert Users

Hi,

I have a few questions about makefiles. I have defined my own version of a dependency file (.d) by creating it in code and called it say .dd. Now this file I have included in the makefile with the include statement. (There are a whole bunch of these files so I've defined this as a rule which uses subst to replace the extension as required.)

Now suppose that file X depends on file Y i.e. X.dd contains a reference to file Y. Now from my understanding, whenever I run make and the program goes through the include and finds that Y has been updated, it somehow recompiles this so as to reflect the changes in X.

My question and problem is when this timestamp change in Y is noticed, does make restart itself so as to include the changes. How exactly are dependency files of this sort resolved. Also file X is not a typical .c or .cc file. So how would the file be treated when its dependency changes.

The problem I'm facing is that if file Y is changed/touched, file X does not recompile. Also if I touch file X, it recompiles just fine. Also as expected, if the makefile is touched, everything recompiles appopriately.

This bug has me scratching my head for a few days now so any help whatsoever would be appreciated.

Please let me know if you need any additional information.

Regards
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Shishir

-----Post Update-----

Further explaining the situation with an example,

Ok so assume that there is this file X.boy where .boy is some internal format. Now this file depends on another file Y.boy which has been included inside X.boy. Now I have hand-coded my own dependency file say X.d which contains these dependencies and I have included this X.d in the makefile using the include statement. Now if I make changes to Y.boy, I would expect the X.d file to detect this change and automatically recompile X.boy. This however does not happen and apparently X.boy fails to pick up this change and recompile.

Cheers
--
Shishir

I assume that by "touched" you mean "changed'. Is this correct?

Thanks for your reply.

Yes. In production it would mean the file was modified but for testing I run a touch command on it on console so the timestamp changes and the file appears modified.

Basically, when a dependency is found to have been modified, does make stop, enter the file to be re-compiled into some internal database and then restart from that point onwards?