Fixed MSVC linker crash.

[kwaegel]

• Linking pcl_features hit 4GB memory limit in release mode. Disabled whole program optimization and link-time code generation as a workaround.

Addresses issue #349.

[jspricke]

I would do it in here: https://github.com/PointCloudLibrary/pcl/blob/master/CMakeLists.txt#L118

[kwaegel]

That would turn off optimization for everything. It is only pcl_features that is having a problem, so I was trying to keep my changes localized to that module.

[jspricke]

But it would still turn it of globally, so I don't see the point of hiding it in there. Also, we should not disable it for people with enough RAM ;).

[kwaegel]

This patch does not turn optimization off globally. Overwriting the variables in CMake only sets them for the current directory and sub-directories (unless the PARENT_SCOPE option is used during SET).

This bug is not due to limited system memory. Selecting "Visual Studio 11 Win64" in CMake defaults to using the x86_amd64 cross-compiler, which is a 32-bit process and can only access 4GB of RAM.

Just discovered:
Visual studio does have a native amd64 compiler, but I can't find a standard way to set that in CMake. This StackOverflow post describes how to change the default toolset to native amd64, but this method was non-obvious (for me) and does not address problems with using the defaults.

Ideally we would only turn this option off if a 32-bit linker is detected, but I'm not sure how to check for that.

[nizar-sallem]

This post suggests that there is a way around that without touching PCL http://stackoverflow.com/questions/14319247/cmake-is-unable-to-configure-project-for-visual-studios-10-amd64 but I can not test it since I don't have a windows machine.

[jspricke]

@kwaegel I wasn't aware of that, sorry. Thanks for the patch