Re: Parallel Build, but Not for the Command-Line Targets.

[dprovan]

The discussion so far has been based on the idea that the user is expressing
an order on the command line and will be surprised if that order is not
followed. That definitely makes sense, and I was quite shocked to discover
this problem. ("make -j clean all" does /what/?!)

But when I ran into this issue a couple months ago, I thought a temporal
prerequisite might be the solution. In other words, give the creator of the
makefile a way to express that there's no requirement to build A just
because you're going to build B, and no reason to rebuild B just because
you've built A, but, nevertheless, if you need to build both A and B, A must
be built first. (As it happens, I'm only on this mailing list because I
thought order-only prerequisites were like that, and I found a discussion
here from a few years ago that straightened me out.)

I claim that a requirement for ordering on the command line is caused, for
the most part, because the user knows what logical order the makefile needs,
and the makefile cannot express the requirement for itself.

-don provan




--
View this message in context: 
http://gnu-make.2324884.n4.nabble.com/Parallel-Build-but-Not-for-the-Command-Line-Targets-tp15766p15791.html
Sent from the Gnu - Make - Bugs mailing list archive at Nabble.com.