Use RBIMPL_COMPILER_{SINCE,BEFORE} for MSVC
Pointed out by @shyouhei (Shyouhei Urabe).
NOTE: Already we have dropped the support for older MSVCs, probably prior to 1300 or 1400. Remove the conditional code, especially in win32/Makefile.sub.
Added by nobu (Nobuyoshi Nakada) almost 5 years ago
Use RBIMPL_COMPILER_{SINCE,BEFORE} for MSVC
Pointed out by @shyouhei (Shyouhei Urabe).
NOTE: Already we have dropped the support for older MSVCs,
probably prior to 1300 or 1400. Remove the conditional code,
especially in win32/Makefile.sub.