parser: fix regression in #; syntax.

A crash has showed up when processing commented-out objects.
This is due to the most recent gc fix to the parser.

* parser.y (set_syntax_tree): Avoid the set macro when tree
has the special value nao (not an object).

* y.tab.c.shipped: Regenerated.

* y.tab.h.shipped: Likewise.

3 files changed, 9 insertions, 3 deletions

diff --git a/parser.y b/parser.y
index 3c51b69d..875a808e 100644
--- a/parser.y
+++ b/parser.y
@@ -1400,7 +1400,10 @@ void yydebug_onoff(int val)
 
 static void set_syntax_tree(parser_t *parser, val tree)
 {
-  set(mkloc(parser->syntax_tree, parser->parser), tree);
+  if (tree == nao)
+    parser->syntax_tree = tree;
+  else
+    set(mkloc(parser->syntax_tree, parser->parser), tree);
 }
 
 static val sym_helper(parser_t *parser, wchar_t *lexeme, val meta_allowed)
diff --git a/y.tab.c.shipped b/y.tab.c.shipped
index 2df3bdb9..526f2eef 100644
--- a/y.tab.c.shipped
+++ b/y.tab.c.shipped
@@ -6743,7 +6743,10 @@ void yydebug_onoff(int val)
 
 static void set_syntax_tree(parser_t *parser, val tree)
 {
-  set(mkloc(parser->syntax_tree, parser->parser), tree);
+  if (tree == nao)
+    parser->syntax_tree = tree;
+  else
+    set(mkloc(parser->syntax_tree, parser->parser), tree);
 }
 
 static val sym_helper(parser_t *parser, wchar_t *lexeme, val meta_allowed)
diff --git a/y.tab.h.shipped b/y.tab.h.shipped
index 19ec4906..82de207d 100644
--- a/y.tab.h.shipped
+++ b/y.tab.h.shipped
@@ -154,7 +154,7 @@ typedef union YYSTYPE
 {
 
 /* Line 2068 of yacc.c  */
-#line 106 "parser.y"
+#line 107 "parser.y"
 
   wchar_t *lexeme;
   union obj *val;