Guard a static assert for MSVC
Guard a static assert for MSVC

MSVC doens't pack diffrent underlying int types into a bitfield. e.g.

  struct S {
    int a: 1;
    char b: 1;
    int c: 1;
  };

These fields are considered three sparate bitfields.

ahoppen/swift,glessard/swift,roambotics/swift,JGiola/swift,rudkx/swift,benlangmuir/swift,JGiola/swift,roambotics/swift,benlangmuir/swift,gregomni/swift,glessard/swift,apple/swift,ahoppen/swift,apple/swift,JGiola/swift,benlangmuir/swift,roambotics/swift,roambotics/swift,atrick/swift,gregomni/swift,ahoppen/swift,ahoppen/swift,glessard/swift,gregomni/swift,atrick/swift,rudkx/swift,benlangmuir/swift,atrick/swift,gregomni/swift,benlangmuir/swift,atrick/swift,ahoppen/swift,rudkx/swift,apple/swift,rudkx/swift,atrick/swift,apple/swift,ahoppen/swift,rudkx/swift,benlangmuir/swift,roambotics/swift,roambotics/swift,gregomni/swift,atrick/swift,JGiola/swift,apple/swift,JGiola/swift,rudkx/swift,glessard/swift,glessard/swift,gregomni/swift,glessard/swift,JGiola/swift,apple/swift