pub const MSVC_IDENTITY_SOURCE: &str = "mbx_msc_ver _MSC_VER\nmbx_msc_full_ver _MSC_FULL_VER\nmbx_msc_build _MSC_BUILD\nmbx_clang __clang__\nmbx_x64 _M_X64\nmbx_x86 _M_IX86\nmbx_arm64 _M_ARM64\nmbx_arm64ec _M_ARM64EC\nmbx_arm _M_ARM\n";Expand description
Source preprocessed to ask cl.exe who it is.
The macros survive unexpanded in any compiler that does not define them, so the answer does not depend on banner wording or the console locale.