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Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type

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Alessandro Basili <alessandro.basili@cern.ch> wrote:
(snip)
> That's another key point it worries me a lot. My goal is not to fix the
> compiler, but start using it to build my program for the aforementioned
> architecture. I would assume the shift/reduce conflicts is resulting
> from an incorrect description of the language, but if I can be able to
> understand what kind of construct of the language will trigger the
> conflict I can probably avoid to use it in my program.

Shift/reduce conflicts are not unusual, and not necessarily bad.

They often come from ambiguities in the language being parsed,
nested if-then-else being a favorite example.  In many languages
with if-then-else, the else is defined to go with the nearest if,
but the syntax description doesn't know that.  Specifying that
resolves the shift/reduce conflict.

Still, it might be worth trying to understand where the
conflicts come from to be sure that it is part of the
language definition.

As I understand it, though, reduce/reduce conflicts are not so
usual, and should be considered errors.

-- glen

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bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type Alessandro Basili <alessandro.basili@cern.ch> - 2011-10-31 14:15 +0100
  Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type Hans Aberg <haberg-news@telia.com> - 2011-10-31 20:49 +0100
    Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type Alessandro Basili <alessandro.basili@cern.ch> - 2011-11-02 09:45 +0100
  Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type George Neuner <gneuner2@comcast.net> - 2011-11-02 12:33 -0400
    Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type George Neuner <gneuner2@comcast.net> - 2011-11-04 12:56 -0400
      Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type Alessandro Basili <alessandro.basili@cern.ch> - 2011-11-06 19:24 +0100
        Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-11-07 05:08 +0000
        Re: bison c-parse.y:1115.19-20: $$ for the midrule at $4 of `structsp' has no declared type George Neuner <gneuner2@comcast.net> - 2011-11-07 03:18 -0500

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