Re: question about Generating Prerequisites Automatically

[Paul D. Smith]

%% Regarding Re: question about Generating Prerequisites Automatically;
%% Lin George <address@hidden> writes:

  lg> I have read through this section before after your recommendation
  lg> previously. Personally, I do not agree with these statements,

I'm not sure what you mean by saying you "do not agree with these
statements".  Do you think they're not true?  Or...?

> But if B is an intermediate file, then `make' can leave well enough
> alone.  It won't bother updating B, or the ultimate target, unless
> some prerequisite of B is newer than that target or there is some
> other reason to update that target.

  lg> The purpose of above statements is to describe the different
  lg> behavior when make deals with intermediate file -- but I have not
  lg> seen any differences because it is the same that make will check
  lg> the prerequisites of B and update B if the prerequisites are
  lg> newer, which behaves the same as the ordinary files.

You have left out the critical context provided by the first sentence in
the paragraph you quoted; the entire paragraph has to be read within
that context:

>    The first difference is what happens if the intermediate file does
> not exist.

For "normal" targets, if the file does not exist it WILL be remade, and
that WILL cause the ultimate target to be remade.

For intermediate files, they won't be remade unless needed, EVEN IF THEY
DON'T EXIST.

-- 
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 Paul D. Smith <address@hidden>          Find some GNU make tips at:
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 "Please remain calm...I may be mad, but I am a professional." --Mad Scientist