Re: Bug in cp/parse.y in 3.1 branch

[Jakub Jelinek <jakub at redhat dot com>]

On Tue, Apr 23, 2002 at 11:27:45AM -0700, David O'Brien wrote:
> yacc: w - line 2120 of "gcc-3_1-branch/gcc/cp/parse.y", $3 references beyond the end of the current rule
> yacc: 33 shift/reduce conflicts
> yacc: 58 reduce/reduce conflicts
> 
> 
> The YACC rule for this is:
> 
>     nomods_initdcl0:
>               notype_declarator maybeasm
>                 { /* Set things up as initdcl0_innards expects.  */
>               $<ttype>3 = $2;
>               $2 = $1;
>                   $<ftype>1.t = NULL_TREE;
>               $<ftype>1.lookups = NULL_TREE; }
>               initdcl0_innards
>                 {}
>         | constructor_declarator maybeasm maybe_attribute
>             { tree d = parse_decl0 ($1, NULL_TREE, NULL_TREE, $3, 0);
>               parse_end_decl (d, NULL_TREE, $2); }
>         ;
> 
> 
> There is not match for the "$<ttype>3" pseudo-variable above.

It is assigned into $3, not read. The whole purpose of the above code
is to move things one slot up, so that it matches what
initdcl0_innards expects (this is described above initdcl0_innards):
        /* This rule assumes a certain configuration of the parser stack.
           In particular, $0, the element directly before the beginning of
           this rule on the stack, must be a maybeasm.  $-1 must be a
           declarator or notype_declarator.  And $-2 must be some declmods
           or declspecs.  We can't move the maybeasm into this rule because
           we need that reduce so we prefer fn.def1 when appropriate.  */
If you revert my patch, you end up violating these assumptions.

	Jakub