Re: Compiler warning cleanup - unitilized const variables, pointer type mismatch

On Thu, May 28, 2009 at 01:51:07PM +0200, Zdenek Kotala wrote:
> Problem is with YYLLOC_DEFAULT. When I look on macro definition
>
> #define YYLLOC_DEFAULT(Current, Rhs, N) \
> Current.first_line = Rhs[1].first_line; \
> Current.first_column = Rhs[1].first_column; \
> Current.last_line = Rhs[N].last_line; \
> Current.last_column = Rhs[N].last_column;
>
> It seems to me that it is OK, because 1 is used as a index which finally
> point on yyerror_range[0].

Wait, this is the bison definition. Well to be more precise the bison
definition in your bison version. Mine is different:

# define YYLLOC_DEFAULT(Current, Rhs, N) \
do \
if (YYID (N)) \
{ \
(Current).first_line = YYRHSLOC (Rhs, 1).first_line; \
(Current).first_column = YYRHSLOC (Rhs, 1).first_column; \
(Current).last_line = YYRHSLOC (Rhs, N).last_line; \
(Current).last_column = YYRHSLOC (Rhs, N).last_column; \
} \
else \
{ \
(Current).first_line = (Current).last_line = \
YYRHSLOC (Rhs, 0).last_line; \
(Current).first_column = (Current).last_column = \
YYRHSLOC (Rhs, 0).last_column; \
} \
while (YYID (0))

Having said that, it doesn't really matter as we redefine the macro:

#define YYLLOC_DEFAULT(Current, Rhs, N) \
do { \
if (N) \
(Current) = (Rhs)[1]; \
else \
(Current) = (Rhs)[0]; \
} while (0)

I have to admit that those version look strikingly unsimilar to me. There is no
reference to Rhs[N] in our macro at all. But then I have no idea whether this
is needed.

Michael
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