[CMake] VS2012 builds using v3.1.0 are a lot slower than v2.8.12

[Brad King]

On 01/20/2015 07:10 AM, Yves Frederix wrote:
>>  msbuild ALL_BUILD.vcxproj /p:Configuration=Release /p:VisualStudioVersion=12.0
> (shouldn't this have been VisualStudioVersion=11.0?)

Yes, but I was testing with VS 2013.

> When keeping an eye on the resource monitor, I can also see that,
> while "cmake --build ." makes use of all the CPU cores (for 2.8.12) ,
> this is not the case while running msbuild manually.

Through 2.8.12.2 the "cmake --build" mode would read the output of
the build and write it again to its own output pipes.  When there
is a lot of output this can probably take some CPU.  There was
an option "--use-stderr" to change to share the pipes so that
they pass through directly to the terminal.  3.0 and above always
do this and the "--use-stderr" option is ignored, so it should not
have that problem.

-Brad