Default to the same flag that is used for verbose link information, but
provide another internal platform information variable to use a
compilation-specific variant. Populate it for CUDA where we use a
different compiler for compilation and linking and therefore need
different flags.
Co-Author: Chuck Cranor <chuck@ece.cmu.edu>
Starting in CUDA 9 the default compilation mode is C++14, and you need
to explicitly enable C++98/03 mode.
While at it, document `14` among the values for `CUDA_STANDARD`. This
was accidentally left out of commit v3.9.0-rc1~118^2 (CUDA: Add support
for the C++14 standard flag, 2017-05-11).
Fix the default values of `CMAKE_CUDA_FLAGS[_<CONFIG>]` on Windows to
make the host compiler flags match those produced for C++ by the
`Platform/Windows-MSVC` module. This makes the flags consistent with
those used for C++.
Port Windows-specific compilation and linking rules over from the
`Platform/Windows-MSVC` module and adapt it for NVIDIA CUDA. On Windows
nvcc and its host compiler (MSVC) do not understand or use options like
`-fPIC` or `-std=`, so condition those out.
Since commit v3.7.0-rc1~392^2 (Honor CMAKE_<LANG>_FLAGS[_<CONFIG>]_INIT
set in toolchain files, 2016-07-05) our convention is to initialize
compiler flag variables via `string(APPEND)` rather than `set()`.
Fix the convention for `CMAKE_CUDA_FLAGS[_<CONFIG>]_INIT`.
