Even if the compiler makes it work for you it's going to be allocated on the stack, it will grow on each call, and that memory will never be released.
This can only degenerate into issues.

I'll try out a scale enabled version someday, need to work out a path that doesn't tank performance.

To adjust shift from anchor point most games have a scale factor of 0-ff and do: scaledShift=(baseShift*(scale+1))>>8