/* Copy into *YYMSG, which is of size *YYMSG_ALLOC, an error message
about the unexpected token YYTOKEN while in state YYSTATE.
- Return 0 if *YYMSG was successfully written. Return 1 if an ordinary
- "syntax error" message will suffice instead. Return 2 if *YYMSG is
- not large enough to hold the message. In the last case, also set
- *YYMSG_ALLOC to either (a) the required number of bytes or (b) zero
- if the required number of bytes is too large to store. */
+ Return 0 if *YYMSG was successfully written. Return 1 if *YYMSG is
+ not large enough to hold the message. In that case, also set
+ *YYMSG_ALLOC to the required number of bytes. Return 2 if the
+ required number of bytes is too large to store. */
static int
yysyntax_error (YYSIZE_T *yymsg_alloc, char **yymsg,
int yystate, int yytoken)
-{
- int yyn = yypact[yystate];
-
- if (! (YYPACT_NINF < yyn && yyn <= YYLAST))
- return 1;
- else
{
YYSIZE_T yysize0 = yytnamerr (0, yytname[yytoken]);
YYSIZE_T yysize = yysize0;
const char *yyformat = 0;
/* Arguments of yyformat. */
char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
+ /* Number of reported tokens (one for the "unexpected", one per
+ "expected"). */
+ int yycount = 0;
+ /* There are many possibilities here to consider:
+ - Assume YYFAIL is not used. It's too flawed to consider. See
+ <http://lists.gnu.org/archive/html/bison-patches/2009-12/msg00024.html>
+ for details. YYERROR is fine as it does not invoke this
+ function.
+ - If this state is a consistent state with a default action, then
+ the only way this function was invoked is if the default action
+ is an error action. In that case, don't check for expected
+ tokens because there are none.
+ - The only way there can be no lookahead present (in yychar) is if
+ this state is a consistent state with a default action. Thus,
+ detecting the absence of a lookahead is sufficient to determine
+ that there is no unexpected or expected token to report. In that
+ case, just report a simple "syntax error".
+ - Don't assume there isn't a lookahead just because this state is a
+ consistent state with a default action. There might have been a
+ previous inconsistent state, consistent state with a non-default
+ action, or user semantic action that manipulated yychar.
+ - Of course, the expected token list depends on states to have
+ correct lookahead information, and it depends on the parser not
+ to perform extra reductions after fetching a lookahead from the
+ scanner and before detecting a syntax error. Thus, state merging
+ (from LALR or IELR) and default reductions corrupt the expected
+ token list. However, the list is correct for canonical LR with
+ one exception: it will still contain any token that will not be
+ accepted due to an error action in a later state.
+ */
+ if (yytoken != YYEMPTY)
+ {
+ int yyn = yypact[yystate];
+ yyarg[yycount++] = yytname[yytoken];
+ if (!yypact_value_is_default (yyn))
+ {
/* Start YYX at -YYN if negative to avoid negative indexes in
YYCHECK. In other words, skip the first -YYN actions for
this state because they are default actions. */
int yyxbegin = yyn < 0 ? -yyn : 0;
-
/* Stay within bounds of both yycheck and yytname. */
int yychecklim = YYLAST - yyn + 1;
int yyxend = yychecklim < YYNTOKENS ? yychecklim : YYNTOKENS;
- /* Number of reported tokens (one for the "unexpected", one per
- "expected"). */
- int yycount = 0;
int yyx;
-
- yyarg[yycount++] = yytname[yytoken];
-
for (yyx = yyxbegin; yyx < yyxend; ++yyx)
if (yycheck[yyx + yyn] == yyx && yyx != YYTERROR
&& !yytable_value_is_error (yytable[yyx + yyn]))
}
yyarg[yycount++] = yytname[yyx];
yysize1 = yysize + yytnamerr (0, yytname[yyx]);
- if (! (yysize <= yysize1 && yysize1 <= YYSTACK_ALLOC_MAXIMUM))
- {
- /* Overflow. */
- *yymsg_alloc = 0;
- return 2;
- }
+ if (! (yysize <= yysize1
+ && yysize1 <= YYSTACK_ALLOC_MAXIMUM))
+ return 2;
yysize = yysize1;
}
+ }
+ }
switch (yycount)
{
case N: \
yyformat = S; \
break
+ YYCASE_(0, YY_("syntax error"));
YYCASE_(1, YY_("syntax error, unexpected %s"));
YYCASE_(2, YY_("syntax error, unexpected %s, expecting %s"));
YYCASE_(3, YY_("syntax error, unexpected %s, expecting %s or %s"));
yysize1 = yysize + yystrlen (yyformat);
if (! (yysize <= yysize1 && yysize1 <= YYSTACK_ALLOC_MAXIMUM))
- {
- /* Overflow. */
- *yymsg_alloc = 0;
- return 2;
- }
+ return 2;
yysize = yysize1;
if (*yymsg_alloc < yysize)
if (! (yysize <= *yymsg_alloc
&& *yymsg_alloc <= YYSTACK_ALLOC_MAXIMUM))
*yymsg_alloc = YYSTACK_ALLOC_MAXIMUM;
- return 2;
+ return 1;
}
/* Avoid sprintf, as that infringes on the user's name space.
}
return 0;
}
-}
#endif /* YYERROR_VERBOSE */
\f
yyerrlab:
/* Make sure we have latest lookahead translation. See comments at
user semantic actions for why this is necessary. */
- yytoken = YYTRANSLATE (yychar);
+ yytoken = yychar == YYEMPTY ? YYEMPTY : YYTRANSLATE (yychar);
/* If not already recovering from an error, report this error. */
if (!yyerrstatus)
int yysyntax_error_status = YYSYNTAX_ERROR;
if (yysyntax_error_status == 0)
yymsgp = yymsg;
- else if (yysyntax_error_status == 2 && 0 < yymsg_alloc)
+ else if (yysyntax_error_status == 1)
{
if (yymsg != yymsgbuf)
YYSTACK_FREE (yymsg);
{
yymsg = yymsgbuf;
yymsg_alloc = sizeof yymsgbuf;
+ yysyntax_error_status = 2;
}
else
{
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