From: NeilBrown <neil@brown.name>
Date: Mon, 10 Jun 2019 06:34:55 +0000 (+1000)
Subject: parsergen: don't report conflicts resolved by precedence.
X-Git-Url: https://ocean-lang.org/code/?p=ocean;a=commitdiff_plain;h=afa1be3c3a7f14a8c476d937a33376490272ba45

parsergen: don't report conflicts resolved by precedence.

If precedence information has been given which can resolve
a conflict, then don't report it.

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

diff --git a/csrc/parsergen.mdc b/csrc/parsergen.mdc
index d12a400..6d29131 100644
--- a/csrc/parsergen.mdc
+++ b/csrc/parsergen.mdc
@@ -1800,14 +1800,20 @@ counted, and are reported as non-critical.  This will not affect a
 				int p = item_prod(itm);
 				int bp = item_index(itm);
 				struct production *pr = g->productions[p];
+				struct symbol *s;
 
-				if (bp < pr->body_size &&
-				    pr->body[bp]->type == Terminal) {
-					/* shiftable */
-					int sym = pr->body[bp]->num;
-					if (symset_find(&shifts, sym) < 0)
-						symset_add(&shifts, sym, itm);
-				}
+				if (bp >= pr->body_size ||
+				    pr->body[bp]->type != Terminal)
+					/* not shiftable */
+					continue;
+
+				s = pr->body[bp];
+				if (s->precedence && is->precedence)
+					/* Precedence resolves this, so no conflict */
+					continue;
+
+				if (symset_find(&shifts, s->num) < 0)
+					symset_add(&shifts, s->num, itm);
 			}
 			/* Now look for reductions and conflicts */
 			for (j = 0; j < is->items.cnt; j++) {