🚀 go-pugleaf

>How would you fix C without breaking a lot of C code?

One "solution" would just be to say "switch to C++", but I assume you mean
something less dramatic.

At the risk of fanning the old comp.lang.c wars, add "noalias".

Whether or not "alias" would be more natural is moot if we don't want to break
existing code.  Similarly, the simple change of having array parameter
declarations recognized as entities which cannot be aliased to other array
parameters would break existing code.

Allow portable constructs (non-portable #pragma's aren't good enough) to
declare when functions have no side effects - or what I think is an equivalent
statement, that the function is purely number-theoretic over its arguments and
return value.  Compilers that can make this determination themselves get bonus
points.

This would make a very good start.