[cmake-developers] [CMake 0014485]: The result of find commands should always have the drive letter included on Windows platforms

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://public.kitware.com/Bug/view.php?id=14485 
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Reported By:                irwin
Assigned To:                
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Project:                    CMake
Issue ID:                   14485
Category:                   CMake
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2013-10-15 12:40 EDT
Last Modified:              2013-10-15 12:40 EDT
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Summary:                    The result of find commands should always have the
drive letter included on Windows platforms
Description: 
This is one of two issues noted on the mailing-list thread started at
http://public.kitware.com/pipermail/cmake-developers/2013-October/008589.html
for Windows systems that happen to have a Linux file hierarchy mounted as a
particular drive letter.  (This scenario always happens on Wine, but it could
also occur on the Microsoft version of Windows systems.)

The test CMake code is as follows:

find_program(LUA_EXECUTABLE lua
  PATHS
  /usr/bin
  NO_DEFAULT_PATH
  )
message(STATUS "LUA_EXECUTABLE = ${LUA_EXECUTABLE}")

When the above is executed from the MSYS bash.exe shell, then the
following result is obtained:

bash.exe-3.1$ cmake -P test.cmake
-- LUA_EXECUTABLE = /usr/bin/lua

This is an obviously incorrect result since /usr/bin/lua does
not exist from the MSYS/Windows system perspective, i.e.,

bash.exe-3.1$ ls /usr/bin/lua
ls: /usr/bin/lua: No such file or directory

If the result of the find command had included the drive letter, then the
result would have been 

-- LUA_EXECUTABLE = z:/usr/bin/lua

and, indeed, that file does exist from the MSYS/Windows perspective:

bash.exe-3.1$ ls z:/usr/bin/lua
z:/usr/bin/lua

The proposed change to always include the drive letter in the results of find
commands on Windows systems has the huge advantage that the results are
guaranteed to exist from the MSYS/Windows perspective making additional
analysis of other find issues (e.g., is the file found the one you want) much
easier.  And I cannot think of a scenario where a user would consider it to be a
good thing for the results of a find command to not exist (like demonstrated
above).  So this proposed change seems a no-brainer to me.
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Issue History 
Date Modified    Username       Field                    Change               
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2013-10-15 12:40 irwin          New Issue                                    
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