Re: inopportune rebuild

From: TEMPLIE Cédric (cedric.templie_at_[hidden])
Date: 2005-02-08 12:10:53

TEMPLIE Cédric wrote:
> TEMPLIE Cédric wrote:
> 
>>David Abrahams wrote:
>>
>>
>>>TEMPLIE Cédric <cedric.templie_at_[hidden]> writes:
>>>
>>>
>>>
>>>
>>>>>Maybe, the "copy" command does not change the timestamps on files, so staged 
>>>>>project2.h is always considered out of date with regard to .rsp and .obj 
>>>>>files, which are generated, and so have current time as timestamp.
>>>>>
>>>>>What happens if you 
>>>>>1. Built everything
>>>>>2. Verify that this problem exists
>>>>>3. Touch project2.h in your tree
>>>>>4. Build again.
>>>>>
>>>>>After that, invoking bjam again should not copy project2.h.
>>>>>
>>>>>And a related question -- what command can be used to update timestamp on 
>>>>>Windows. On Unix, it's just "touch", but that command is not present on 
>>>>>Windows by default.
>>>>>
>>>>
>>>>Thanks :) you are totally right, the timestamp is not changed, so it 
>>>>tries to rebuild (copy) :(
>>>>And it seems that it is the same for rsp files....
>>>>The only way I found to change the date is to modify the file (like that 
>>>>the modification access date change), but I am looking for a better 
>>>>solution. I found some tools (a touch for windows) to do that, but these 
>>>>tools are not natively with windows :(
>>>>
>>>>So have you got a solution to change the timestamp when copying, or 
>>>>another idea ?
>>>
>>>
>>> TYPE file1 > file2
>>>
>>>?
>>>
>>
>>
>>I try that, and in fact timestamps changed... :)
>>What are the change to do for using TYPE instead of copy ? or maybe it 
>>will be change for next milestone ?
>>
>>Thanks again
>>
>>TEMPLIE Cédric
>>
> 
> 
> I use the cygwin cp, I just set the CP var in common.jam. Now my system 
> works very better :)
> 
> Maybe that could be add in a documentation to explain that windows copy 
> does not change timestamps, and it causes a lot of inopportune rebuilds...
> 
> But, again, thanks for your help.
> 
> TEMPLIE Cédric
> 

As I already said, I think that there is also an issue with rsp files.. 
indeed timestamps of rsp files seems to not change everytime too, and it 
causes rebuild...
I found a way to update timestamps for the copy, but what can i do for 
rsp files ?

Thanks for your help

TEMPLIE Cédric