[cmake-developers] [CMake 0012564]: Repeated git clones and build for external projects on Windows

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://cmake.org/Bug/view.php?id=12564 
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Reported By:                Andras Lasso
Assigned To:                
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Project:                    CMake
Issue ID:                   12564
Category:                   CMake
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
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Date Submitted:             2011-11-08 12:19 EST
Last Modified:              2011-11-08 12:19 EST
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Summary:                    Repeated git clones and build for external projects
on Windows
Description: 
It's extremely frustrating to use git external projects on Windows, mainly due
to two problems.

1. CMake&git keeps downloading and building the project many times. This takes
very long time on projects using VTK, ITK, Slicer, CTK, etc.

2. Many directory deletes that seems to occur during simple update/rebuild
operations. If they fail to complete (because the directory is in use) then it
leads to permanent git errors.

msysgit: 1.7.7.msysgit.1
TortoiseGit: 1.7.3.0

Steps to Reproduce: 
1. Typical use case for re-clone and re-build problem:
-Start build in debug mode => git clone, re-build
-Start build in release mode => git clone(!), re-build
-Start build in debug mode => re-build(!)

This means that when building a project in two modes it does an extra clone and
build step, which takes 2-3 hours on a larger project.

2. Typical use case for directory delete problem:
-Start build in debug mode
-Run the application in debug mode, keep the subproject binary directory
(c:\devel\cmakegittest\cmakegittest-superbuild-bin4\cmakegittest-bin) as the
current directory in the command-line window 
-Start build in release mode => build fails due to
"C:/devel/cmakegittest/cmakegittest-superbuild-bin4/cmakegittest" directory
cannot be deleted - note that this is not the directory that was kept in the
current command-line window

1>------ Build started: Project: cmakegittest, Configuration: Release Win32
------
1>Performing download step (git clone) for 'cmakegittest'
1>Error removing directory
"C:/devel/cmakegittest/cmakegittest-superbuild-bin4/cmakegittest".
1>CMake Error at cmakegittest-prefix/tmp/cmakegittest-gitclone.cmake:10
(message):
1>  Failed to remove directory:
1>  'C:/devel/cmakegittest/cmakegittest-superbuild-bin4/cmakegittest'
1>Project : error PRJ0019: A tool returned an error code from "Performing
download step (git clone) for 'cmakegittest'"
1>Build log was saved at
"file://c:\devel\cmakegittest\cmakegittest-superbuild-bin4\cmakegittest.dir\Release\BuildLog.htm"
1>cmakegittest - 1 error(s), 0 warning(s)
2>------ Skipped Build: Project: ALL_BUILD, Configuration: Release Win32 ------
2>Project not selected to build for this solution configuration 
========== Build: 0 succeeded, 1 failed, 1 up-to-date, 1 skipped ==========

All repeated build attempts fail. The
c:\devel\cmakegittest\cmakegittest-superbuild-bin4\cmakegittest cannot be opened
in explorer. Killing the TGitCache.exe process solves the problem: the
c:\devel\cmakegittest\cmakegittest-superbuild-bin4\cmakegittest directory
disappears and repeated build attempts succeed.


Additional Information: 
Attached a sample CMakeLists.txt with that the above reported problems can be
easily reproduced (it downloads and builds a small sub-project from github).
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Issue History 
Date Modified    Username       Field                    Change               
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2011-11-08 12:19 Andras Lasso   New Issue                                    
2011-11-08 12:19 Andras Lasso   File Added: CMakeLists.txt                    
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