[CMake] Intel C99 standard

[Brad King]

On 09/15/2015 05:53 AM, Daniel Wirtz wrote:
> because cmake did not add the "-std=c99" c flags.
> so has that simply not come up yet or is there a reason cmake does not 
> add those flags for intel?

The necessary tables of information have simply not been filled out
for the Intel compiler.  No one has stepped forward to do it so far,
and it requires non-trivial research and testing.

One must construct a table of what versions of Intel support what
standards, and what the corresponding -std= flags are.  There also
need to be tables of which features:

 http://www.cmake.org/cmake/help/v3.3/prop_gbl/CMAKE_C_KNOWN_FEATURES.html
 http://www.cmake.org/cmake/help/v3.3/prop_gbl/CMAKE_CXX_KNOWN_FEATURES.html

are supported by each version of the compiler.  These are encoded
as preprocessor conditional test fragments.  See
Modules/Compiler/GNU-CXX-FeatureTests.cmake for an example.

-Brad