From: NeilBrown <neil@brown.name>
Date: Sun, 9 Jun 2019 22:35:36 +0000 (+1000)
Subject: parsergen: include virtual symbols in table of non-terminals
X-Git-Url: https://ocean-lang.org/code/?p=ocean;a=commitdiff_plain;h=5281589bf4d9a66ce106b160e1272f1c51d7ac15

parsergen: include virtual symbols in table of non-terminals

Symbol numbers assigned in grammar_analyse are in three groups:
 - predefined (NUMBER, STRING, etc)
 - Terminals
 - everything else: non-terminals and virtual.

When creating the non_term[] list of names, we need to include
virtual symbols in there, otherwise lookup by symbol-number
might find the wrong value - or might reach beyond end of array.

Signed-off-by: NeilBrown <neil@brown.name>
---

diff --git a/csrc/parsergen.mdc b/csrc/parsergen.mdc
index 478482e..d2ff898 100644
--- a/csrc/parsergen.mdc
+++ b/csrc/parsergen.mdc
@@ -1900,7 +1900,9 @@ pieces of code provided in the grammar file, so they are generated first.
 ### Known words table
 
 The known words table is simply an array of terminal symbols.
-The table of nonterminals used for tracing is a similar array.
+The table of nonterminals used for tracing is a similar array.  We
+include virtual symbols in the table of non_terminals to keep the
+numbers right.
 
 ###### functions
 
@@ -1925,7 +1927,7 @@ The table of nonterminals used for tracing is a similar array.
 		for (i = TK_reserved;
 		     i < g->num_syms;
 		     i++)
-			if (g->symtab[i]->type == Nonterminal)
+			if (g->symtab[i]->type != Terminal)
 				fprintf(f, "\t\"%.*s\",\n", g->symtab[i]->name.len,
 					g->symtab[i]->name.txt);
 		fprintf(f, "};\n\n");