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Re: gcc (Re: porting?)

On Tue, 10 Feb 1998, Jan Paul Schmidt wrote:
> On Fri, 6 Feb 1998, Tamminen Eero wrote:
> > What about -mpcrel?  Doesn't it do (about) the same thing?
> > 
> > I usually use '-mbaserel -mpcrel -fomit-frame-pointer -O2' as
> > it produces the smallest code (GCCs <= 2.5.8).
> I use that to on, but it won't work always with larger stuff.

What does the -mpcrel actually do? At least newer gcc's use pc relative 
addressing when possible anyway. -mbaserel is sensitive for const stuff. 
If there's 'const int something = 1;' statement somewhere and it is also 
used on other file and declared as 'extern int something;' linking 
doesn't work. The variable is allocated in text section and addressed 
as absolute mode but the 'extern int' without const means that it is 
allocated in data or bss sections and addressed as relative to base 
register. 'extern const int something;' fixes things. 

I was just wondering can the sys_errlist[] be declared as 

extern const char *const sys_errlist[]; 

or is there some kind of standard for it? That would give as a chance to 
keep the whole array on text section which would save that valuable data 
and bss for other things with baserel. There's probably other similar 
things in the mintlib. e.g. localtim.c has two too big static arrays. 

** One of those Atari archive maintainers at ftp.funet.fi