When testing CMAKE_<LANG>_COMPILER_ID values, do not explicitly
dereference or quote the variable. We want if() to auto-dereference the
variable and not its value. Also replace MATCHES with STREQUAL where
equivalent.
CMake defines MSVC only for a VS compiler, but the Intel compiler adds
the preprocessor definition _MSC_VER. Instead of relying on separate
tests to decide whether to use example_dll_2, we do one test in CMake
and then add our own preprocessor definition.
This adds a "ModuleDefinition" test enabled when using MSVC tools. It
checks that .def files can be used to export .dll and .exe symbols and
create corresponding .lib files that can be linked. See issue #9613.
Ben Boeckel
Brad King