[CMake] Building an object with spaces in path

[Richard Moreland]

Hi,

I have a problem when building an object that resides in a path with 
spaces.  I have the following source tree:

/test
   CMakeLists.txt
   two words/
      CMakeLists.txt
      main.cpp

When I attempt to build this (in or out of source, using the generated 
Makefile), I get:

make[2]: Entering directory `/home/richard/cmtest/build'
Building CXX object two words/CMakeFiles/main.dir/main.o
/usr/bin/c++    -o two words/CMakeFiles/main.dir/main.o -c 
/home/richard/cmtest/two\ words/main.cpp
c++: cannot specify -o with -c or -S and multiple compilations
make[2]: *** [two words/CMakeFiles/main.dir/main.o] Error 1

The error is in the -o argument, because "two words" doesn't get escaped 
properly.

I poked at the source a bit and saw that the rule is using an object 
filename that never gets escaped properly with ConvertToOutputPath(). 
There is code in cmMakefileTargetGenerator::WriteObjectBuildFile() that 
will run the path through ConvertToOutputPath(), but only if 
CMAKE_WINDOWS_OBJECT_PATH is defined.

Defining it fixes my problem, but it seems like the relativeObj should 
always be escaped properly before it is put into the RuleVariables.Object.

Here is a link to test project demonstrating problem: 
http://ncogni.to/cmake_space_error.tar.gz

Thanks for a great tool.

-Richard