Go patch committed: Better parses

[Ian Lance Taylor]

This patch to the Go frontend improves the parsing of a non-identifier
on the left hand side of :=, and of a non-type in a type switch.
Bootstrapped and ran Go testsuite on x86_64-unknown-linux-gnu.
Committed to mainline.

Ian


diff -r ffdb8cbbc880 go/parse.cc
--- a/go/parse.cc	Fri Sep 23 08:28:44 2011 -0700
+++ b/go/parse.cc	Fri Sep 23 14:51:52 2011 -0700
@@ -3506,7 +3506,21 @@
   else if (return_exp != NULL)
     return this->verify_not_sink(exp);
   else
-    this->expression_stat(this->verify_not_sink(exp));
+    {
+      exp = this->verify_not_sink(exp);
+
+      if (token->is_op(OPERATOR_COLONEQ))
+	{
+	  if (!exp->is_error_expression())
+	    error_at(token->location(), "non-name on left side of %<:=%>");
+	  while (!token->is_op(OPERATOR_SEMICOLON)
+		 && !token->is_eof())
+	    token = this->advance_token();
+	  return NULL;
+	}
+
+      this->expression_stat(exp);
+    }
 
   return NULL;
 }
@@ -4287,8 +4301,19 @@
       while (true)
 	{
 	  Type* t = this->type();
+
 	  if (!t->is_error_type())
 	    types->push_back(t);
+	  else
+	    {
+	      token = this->peek_token();
+	      while (!token->is_op(OPERATOR_COLON)
+		     && !token->is_op(OPERATOR_COMMA)
+		     && !token->is_op(OPERATOR_RCURLY)
+		     && !token->is_eof())
+		token = this->advance_token();
+	    }
+
 	  if (!this->peek_token()->is_op(OPERATOR_COMMA))
 	    break;
 	  this->advance_token();