[cmake-developers] Adding Swift support to CMake for Linux/Makefiles

[Eric Wing]

I'm finding that I'm going to need to completely separate the C FLAGS
from the Swift FLAGS. I hit some complicated situations where the C
FLAGS (both compile and linker) are confusing the process and
shouldn't be passed to Swift.

I see in the CMakeSwiftInformation.cmake, there is a
<CMAKE_Swift_LINK_FLAGS>. However, I do not see a <CMAKE_Swift_FLAGS>,
just <FLAGS>.

Additionally, in regular CMake script, I was trying to set/use
${CMAKE_Swift_FLAGS} hoping it would just work, but it doesn't seem to
have any effect. Is this something I'm going to have to implement in
the C++ core?

Thanks,
Eric