Generator "NMake Makefiles" produces buggy Makefile(s)

[rwiesen]

Platform: Windows (Windows 8.1 64bit, Visual Studio 2015 and Visual Studio 2010)
Version: 0d79118
CMake version: 3.3.2 (download)

Steps to reproduce:

• checkout to directory opencv
• create directory tmp as sibling of opencv
• change to directory tmp
• call 'cmake -G "NMake Makefiles" ..\opencv'
• call 'nmake'

Expected behavior:

• OpenCV is built

Observed behavior:

• nmake stops with an error (translated: path not found):

  [ 2%] Linking C static library ..\lib\zlibd.lib
  Das System kann den angegebenen Pfad nicht finden.
  NMAKE : fatal error U1077: 'cd' : return code '0x1'
  Stop.
  NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\amd64\nmake.exe"' : return code '0x2'
  Stop.
  NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\amd64\nmake.exe"' : return code '0x2'
  Stop.

This error is caused by a trailing backslash for a 'cd' command in the file "...\tmp\3rdparty\zlib\CMakeFiles\zlib.dir\build.make" (line 642 and others) that leads to lines being combined.

[StevenPuttemans]

Could you suggest a fix through a pull request? That will speed up the fixing!

[rwiesen]

No, unfortunately not, as I am an absolute beginner with CMake.

I can't even tell if the bug is in OpenCV or the CMake generator :-(

[alalek]

Try to use "Visual Studio" generators, they are faster than NMake (NMake provides poor support for parallel compilation).
You can refer to commands from our testing infrastructure:
http://pullrequest.opencv.org/buildbot/builders/precommit_windows64

[rwiesen]

Well, I know that the VS generator works - this is my current workaround... ;-)

Nevertheless, if "NMake Makefiles" is offered, it should work. I'd rather use nmake than devenv for automated builds.

[mshabunin]

I think it is a cmake problem, similar issue has been mentioned here: https://cmake.org/pipermail/cmake/2015-September/061484.html

As a workaround you can try to turn CMAKE_USE_RELATIVE_PATHS option OFF (this option is forced to ON in opencv/CMakeLists.txt). But I'd recommend to use VS generator as we do for our automated builds.

[MarianMMX]

1. Open CMakeLists.txt .
2. Go to line 70.
3. Comment (or delete):
   #if(MSVC)

   set(CMAKE_USE_RELATIVE_PATHS ON CACHE INTERNAL "" FORCE)

   #endif()
4. delete the generated files and rerun cmake.

[happyLiMing]

I think it is a problem when you using the VC(cl.exe && nmake.exe).maybe there is some ENV you missed.