Bring back setting the MSYS variable under MSYS2, it's still being used
in a few places.
Link the SDL2::SDL2-static target for static builds.
Add -static-libgcc and -static-libstdc++ to the gcc/clang toolchain for
static builds.
Edit wxWidgets_LIBRARIES under MSYS2 to specify liblzma.a explicitly
because for some reason it's not being linked statically by default for
static builds.
Signed-off-by: Rafael Kitover <rkitover@gmail.com>
* Bring the wx frontend more in-line with the rest of the codebase.
* Always default to Unicode APIs on Windows.
* Clean up all include guards and headers.
* Use add_compile_definitions everywhere.
* Remove unused intermediate target.
* Add ASAN support for MSVC.
* Remove duplicate option definitions.
* Configure MinGW separately from the toolchain
* Move toolchain-specific options to their own files.
* Clean up and modernize the use of toolchain options.
* Use modern cmake LTO support.
* Remove dead cmake code and cmake functions available in upstream cmake.
* Update README.md to remove references to removed build options.
Rafael Kitover