frerich / clcache

A compiler cache for MSVC, much like ccache for gcc
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Infinite recursion while finding cl.exe #312

Open nyanpasu64 opened 6 years ago

nyanpasu64 commented 6 years ago

I have quite a complex setup, with a "path" folder stored under %userprofile%/Dropbox/encrypted/dirlinks/path, and symlinked to %userprofile%/encrypted/dirlinks/path and %userprofile%/path. I also have ConEmu installed.

I only added %userprofile%/path to my PATH variable, while building in Visual Studio.

When I copy clcache.exe to cl.exe and execute it, it enters infinite recursion, unless:

  1. %CD% current directory does not contain cl.exe.
  2. %PATH% contains the normalized path to path folder, and not a path to that folder, but containing symlinks along the way.

If 2 is not true, findCompilerBinary() returns the wrong path since myExecutablePath() (sys.executable.upper()) differs from path.upper() (from %PATH%), even if cl.exe is the same file, accessed via different symlinks.

If 1 is not true, I don't know what's wrong since I don't know how to debug py2exe programs.


I could set CLCACHE_CL, but the default folder differs by host and EXE architecture, making me feel somewhat uncomfortable about setting it up (hard-coded to match one VS project and configuration).


Maybe you should use os.path.realpath(...) or Path.resolve() to normalize paths, to fix 2. I'm not sure if that will fix 1.

nyanpasu64 commented 6 years ago

I tried running a build in Visual Studio with CLCACHE_CL set. The build never started (I'm not sure if CLCACHE_CL was passed into clcache.exe properly) complained CL.exe path was too long (must be below 260 characters or something). Ctrl-F through Diagnostic logs showed that error was the only occurrence of cl.exe (it never got called).


In [5]: from pathlib import Path

In [13]: Path('/users/jimbo1qaz/path').resolve()
Out[13]: WindowsPath('C:/Users/jimbo1qaz/Dropbox/encrypted/dirlinks/path')

In [14]: Path('/users/jimbo1qaz/path').resolve() ==  Path('/users/jimbo1qaz/dropbox/encrypted/dirlinks/path').resolve()
Out[14]: True

In [15]: Path('/users/jimbo1qaz/path') ==  Path('/users/jimbo1qaz/dropbox/encrypted/dirlinks/path')
Out[15]: False

In [16]: Path('/users') == Path('/Users')
Out[16]: True

In [17]: os.path.realpath('/users') ==  os.path.realpath('/userS')
Out[17]: False

Pathlib was introduced in 3.4. Apparently you've dropped Python 3.3 and 2.x already.

nyanpasu64 commented 6 years ago

I'd send a pull request, but this project seems unmaintained.