[FFmpeg-trac] #3650(build system:new): configure fails for VS2013 if environment variable 'CL' was set

[FFmpeg]

#3650: configure fails for VS2013 if environment variable 'CL' was set
-------------------------------------+-------------------------------------
             Reporter:  onsager      |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  build        |                  Version:
  system                             |  unspecified
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:

 Certain values for the environment variable 'CL' on Windows break MSVC-
 based builds.

 How to reproduce:

 Set CL to '/MP' (or similar arguments containing forward slashes)

 On several occasions (configure and actual build) msys path conversion
 kicks in and mangles the environment variable into something like
 'c:\mingw\msys\1.0\MP', leading to missing bogus files for compiler and
 linker.

 Solution:

 set 'CL' to '-MP' or similar. The error is not ffmpegs fault but hard to
 identify, and should at least be mentioned at documentation level:

 https://www.ffmpeg.org/platform.html#Microsoft-Visual-C_002b_002b-or-
 Intel-C_002b_002b-Compiler-for-Windows

--
Ticket URL: <https://trac.ffmpeg.org/ticket/3650>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker