(bison.info)Stack Overflow


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Stack Overflow, and How to Avoid It
===================================

   The Bison parser stack can overflow if too many tokens are shifted
and not reduced.  When this happens, the parser function `yyparse'
returns a nonzero value, pausing only to call `yyerror' to report the
overflow.

   By defining the macro `YYMAXDEPTH', you can control how deep the
parser stack can become before a stack overflow occurs.  Define the
macro with a value that is an integer.  This value is the maximum number
of tokens that can be shifted (and not reduced) before overflow.  It
must be a constant expression whose value is known at compile time.

   The stack space allowed is not necessarily allocated.  If you
specify a large value for `YYMAXDEPTH', the parser actually allocates a
small stack at first, and then makes it bigger by stages as needed.
This increasing allocation happens automatically and silently.
Therefore, you do not need to make `YYMAXDEPTH' painfully small merely
to save space for ordinary inputs that do not need much stack.

   The default value of `YYMAXDEPTH', if you do not define it, is 10000.

   You can control how much stack is allocated initially by defining the
macro `YYINITDEPTH'.  This value too must be a compile-time constant
integer.  The default is 200.


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Dirfile and infopages generated Sat Dec 3 02:07:54 2005