RULES pragmas

[Malcolm Wallace]

dons at cse.unsw.edu.au (Donald Bruce Stewart) wrote:

> > So what am I doing wrong?  And is there any way to ask the compiler
> > to give a warning if the RULES pragma contains errors?
> 
> In this case, it's because it's missing -fglasgow-exts, I think.

Ah, thank you.  The missing (and undocumented) option.  Is there any
reason why -fglasgow-exts should be required?  Judging by the flag
reference material in section 4.17.15, -frules-off is used to turn RULES
off explicitly, but there is no corresponding flag to turn them on -
hence I assumed they would be enabled by default when -O or -O2 is set.

Regards,
    Malcolm