[CMake] Buggy progress reporting

[Michael Wild]

On 26. Jan, 2009, at 15:05, Jesper Eskilson wrote:

> Bill Hoffman <bill.hoffman at kitware.com> writes:
>
>> Gopala Krishna wrote:
>>> On Mon, Jan 26, 2009 at 2:29 AM, Bill Hoffman <bill.hoffman at kitware.com 
>>> > wrote:
>>>
>>>> The progress reporting only supports one make at a time in the  
>>>> build tree.
>>>>
>>>> -Bill
>>>>
>>>
>>> Is there any documentation somewhere on how the percentage reporting
>>> is implemented ? If not it would really be helpful atleast to get a
>>> hint on which source files to look at. :)
>>>
>>>
>> No, not really, it uses a directory to communicate, and cmake -E
>> cmake_progress_start.  If you grep for progress in the source tree  
>> and
>> look at the Makefiles you can get the idea.  It is going to be very
>> hard to make it work with more than one make in a tree.
>
> If the directory used for communication had a pid as part of its name,
> wouldn't that solve it? Or is it more complicated than that? (I'm just
> curious.)

Lets say with process 1000 is building target A. Process 2000 is  
building target B at the same time. What happens if both depended on  
target C (e.g. a library) and tried to build it at the same time  
without knowing that there is another process trying to do the very  
same thing. This might lead to very buggy builds...

I don't think this is anything CMake could ever possibly handle, as it  
also very strongly depends on the native build system (Make, VS,  
Xcode,...)

Michael