errors as reported on macOS w/ Xcode 10.1, 10.2 and 11.0:

src/ir.cpp:23285:16: error: variable 'bits' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
    } else if (float_type->id == ZigTypeIdFloat)
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/ir.cpp:23288:13: note: uninitialized use occurs here
    switch (bits) {
            ^~~~
src/ir.cpp:23285:12: note: remove the 'if' if its condition is always true
    } else if (float_type->id == ZigTypeIdFloat)
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/ir.cpp:23281:18: note: initialize the variable 'bits' to silence this warning
    unsigned bits;