Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ALLSPICE.LCS.MIT.EDU!shep
From: shep@ALLSPICE.LCS.MIT.EDU (Tim Shepard)
Newsgroups: gnu.gcc.bug
Subject: mysterious "make -n"
Message-ID: <8902170341.AA13319@PTT.LCS.MIT.EDU>
Date: 17 Feb 89 03:41:17 GMT
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I discovered the same funniness when I typed "make -n install" after
finishing the bootstraping.  I think I understand what is going on.
(Well at least I'm not loosing sleep over this any more.)

When make is being used normally it rechecks the date on a file after
running all the rules that have it as a target.  If the date has not
changed, then make does not trigger the subsequent targets which depend
on the current target.  When you do "make -n", make assumes that the
target always gets updated.  (What else could it do?)

So, it seems that "make -n" can not show exactly what would happen if
you ran make.   Shucks.

			-Tim