[cmake-developers] [CMake 0014597]: Ninja: several add_custom_command(Target ... POST_BUILD ...) may lead to a command which breaks the command line limit

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://public.kitware.com/Bug/view.php?id=14597 
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Reported By:                tisi
Assigned To:                
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Project:                    CMake
Issue ID:                   14597
Category:                   CMake
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
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Date Submitted:             2013-11-26 04:17 EST
Last Modified:              2013-11-26 04:17 EST
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Summary:                    Ninja: several add_custom_command(Target ...
POST_BUILD ...) may lead to a command which breaks the command line limit
Description: 
We encountered the following problem with a project for an embedded
microcontroller, but it is reproducable on normal x86 machines. We use the
command add_custom_command(Target <Target> POST_BUILD <Commands>) to run
severeal commands after linking (some hex-file manipulations like calculating
crc32, moving of memory and so on).

In the past we used the makefile generator and our project worked fine, but we
want to switch to ninja for some other reasons. 

We found the following issue:
The ninja generator combines the linker command and all the add_custom_commands
to one large command (all commands are combinded by &&, so linker-command &&
custom1 && custom2 && custom3 && ...), which breaks the command line limit of
windows (8kB). I think the same issue would be true on linux with an higher
limit (i think 32kb).

Is it possible to change the behavior of the generator to support something like
that (e.g. intermediate targets for the add_custom_commands)? Right now we make
a shell script and use only one add_custom_command, but its not nice that there
is a different behavior between the make and the ninja build at all.

Steps to Reproduce: 
I've uploaded a file with a cmake project, which demonstrates that. You will
need a c compiler, but it doesn't matter which one.

Just run
cmake -G "Ninja" <source_path> && ninja
on Windows and you should see the issue.
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Issue History 
Date Modified    Username       Field                    Change               
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2013-11-26 04:17 tisi           New Issue                                    
2013-11-26 04:17 tisi           File Added: AddCustomCommandDemo.zip            
       
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