RFC: #pragma optimization_level

[Georg Bauhaus]

Robert Dewar wrote:
> A little note is that Ada has a pragma Opimize that would make
> use of this feature (it's currently pretty much ignored).

Though what GCC does for a compilation unit with Ada's pragma
Optimize(Off); inside it is close to what some users seem to be wanting
in C.
GCC does complain about an attempt to translate the program below
with optimization turned on:

$ gcc -gnatv -c -O2 opt.adb
...
     2.    pragma optimize(Off);
           |
        >>> warning: must specify -O0


procedure Opt is
   pragma Optimize(Off);
begin
   for k in 1 .. 1_000_000 loop
      null;
   end loop;
end Opt;