add compile-error test: bitcast
add compile-error test: bitcast

Issue fixed by an unknown commit.

closes #3818

zig-lang/zig,raulgrell/zig,zig-lang/zig,raulgrell/zig,andrewrk/zig,zig-lang/zig,raulgrell/zig,raulgrell/zig,andrewrk/zig,raulgrell/zig