Re: how to identify the prerequisite causing the build?

[Paul Smith]

On Thu, 2011-12-08 at 00:28 -0500, Martin d'Anjou wrote:
> Hi,
> 
> I run make with -d, but there are thousands and thousands of lines... I 
> am not expecting a re-build, but make thinks a rebuilt is in order. The 
> problem is that I cannot find why make thinks this is the right thing to 
> do. Based on what make wants to build, no prerequisite is missing, but 
> how do I get make to tell me exactly the chain of prerequisites that 
> causes the rebuild?
> 
> I do not find a "File does not exist" message, or a missing 
> prerequisite, all I see is "Prerequisite is older than target". What 
> should I look for?

There are lines like this:

       Prerequisite `stamp-h1' is newer than target `config.h'.

If you use --debug=b for basic debugging only, then many of the other
lines won't be printed.

-- 
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