Re: [Cobolforgcc-devel] yacc/bison question

[Tim J. <te...@me...>]

Matthew,

Good to hear from you.

There is no LOCK MODE in COBOL 85, so you can just omit it (for
now). It is only in COBOL 2002.

The problem appears to be due to the fact that the LOCK could be
the start of a LOCK ON MULTIPLE or the start of a second
occurrence of the LOCK MODE clause.

You basically have the right answer. Function set_up_magic_tokens
will need to be updated to change the first LOCK to a magic token
like LOCK_magic_starts_whole_clause. The logic for this would be
if it is not followed by ON, RECORD or RECORDS it must be the
first one.

If this makes no sense, please send me *all* the files. 

Are you in a position to do a copyright assignment to the free
software foundation for this work. I will attach the files which
explain it all. Without the assignments we will not be able to
have the compiler incorporated into the official GCC. Please have
a look.

Tim Josling

Matthew Vanecek wrote:
> 
> Tim,
> I was working on my file i/o grammar this weekend, and ran into some
> issues with the LOCK MODE clause.  I've kinda got it figured out, but
> I'm not certain that it's the correct way:
> 
> I've got a clause:
> 
> LOCK [MODE IS] {MANUAL | AUTOMATIC} [[WITH] LOCK ON {RECORD | RECORDS}]
> 
> The two LOCKs were causing reduce/reduce errors.  I finally ended up
> sticking a "LOCK_ON" token in cobctok.def to alleviate the ambiguity for
> bison/yacc.  I'm a little worried about the kvalue, however.  I've set
> it to "LOCK ON".  I'd like to figure out a way to delete that token, and
> still not have any shift/reduce or reduce/reduce errors.
> 
> Here's the relevant bit from my file.tpl:
> 
> lock_mode_clause:
> LOCK opt_mode opt_is manual_or_auto_kw opt_lock_on_clause {
>         RSN($1, "Lock Mode not yet supported");
> }
> ;
> 
> manual_or_auto_kw:
> MANUAL
> | AUTOMATIC
> ;
> 
> opt_lock_on_clause:
> /* nothing */
> | with_lock_on
> ;
> 
> with_lock_on:
> opt_with lock_on
> ;
> 
> lock_on:
> LOCK_ON record_or_records
> ;
> 
> record_or_records:
> RECORD
> | RECORDS
> ;
> 
> If I change the "LOCK_ON" to "LOCK ON", I get a reduce/reduce error.  I
> would rather not have any errors, but I'm still a little dubious about a
> "LOCK_ON" token.
> 
> Thoughts?
> --
> Matthew Vanecek
> perl -e 'print
> $i=pack(c5,(41*2),sqrt(7056),(unpack(c,H)-2),oct(115),10);'
> ********************************************************************************
> For 93 million miles, there is nothing between the sun and my shadow
> except me.
> I'm always getting in the way of something...
> 
>   -----------------------------------------------------------------
>    Part 1.2Type: application/pgp-signature