From b6f59358b5ae896b523ceb319dbd23d4a0744b5c Mon Sep 17 00:00:00 2001
From: Ken Thompson <ken@golang.org>
Date: Mon, 29 Sep 2008 20:33:51 -0700
Subject: [PATCH] minor bugs

R=r
OCL=16163
CL=16163
---
 src/cmd/gc/export.c |  4 ++++
 src/cmd/gc/go.h     |  3 +--
 src/cmd/gc/go.y     | 14 ++++++--------
 src/cmd/gc/walk.c   | 24 +++++++++++-------------
 4 files changed, 22 insertions(+), 23 deletions(-)

diff --git a/src/cmd/gc/export.c b/src/cmd/gc/export.c
index 50d1e3bdfd..94147ffe16 100644
--- a/src/cmd/gc/export.c
+++ b/src/cmd/gc/export.c
@@ -176,6 +176,10 @@ dumpexporttype(Sym *s)
 	case TPTR64:
 		if(t->type == T)
 			fatal("dumpexporttype: ptr %S", s);
+		if(t->type->etype == TFORW) {
+			yyerror("export of a undefined forward reference: %S", s);
+			break;
+		}
 		makeexportsym(t->type);
 		ts = t->type->sym;
 		if(ts->exported == 0)
diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index 45716c362b..024cd8dcef 100644
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -265,8 +265,7 @@ enum
 	ONAME, ONONAME,
 	ODOT, ODOTPTR, ODOTMETH, ODOTINTER,
 	ODCLFUNC, ODCLFIELD, ODCLARG,
-	OLIST, OCMP,
-	OPTR, OARRAY,
+	OLIST, OCMP, OPTR, OARRAY,
 	ORETURN, OFOR, OIF, OSWITCH,
 	OAS, OASOP, OCASE, OXCASE, OFALL, OXFALL,
 	OGOTO, OPROC, ONEW, OEMPTY, OSELECT,
diff --git a/src/cmd/gc/go.y b/src/cmd/gc/go.y
index 69b7c76d0d..74af515881 100644
--- a/src/cmd/gc/go.y
+++ b/src/cmd/gc/go.y
@@ -800,8 +800,11 @@ pexpr:
 	}
 |	convtype '{' keyexpr_list '}'
 	{
-		// struct literal and conversions
-		$$ = nod(OCONV, rev($3), N);
+		// composite literal
+		$$ = rev($3);
+		if($$ == N)
+			$$ = nod(OEMPTY, N, N);
+		$$ = nod(OCONV, $$, N);
 		$$->type = $1;
 	}
 |	fnliteral
@@ -1266,11 +1269,6 @@ structdcl:
 			$$->type = types[TINT32];
 		};
 	}
-|	LIMPORT structdcl
-	{
-		$$ = $2;
-		$$->etype = OIMPORT;
-	}
 
 interfacedcl:
 	new_name ',' interfacedcl
@@ -1695,7 +1693,7 @@ hidden_importfield:
  * to check whether the rest of the grammar is free of
  * reduce/reduce conflicts, comment this section out by
  * removing the slash on the next line.
- *
+ */
 lpack:
 	LATYPE
 	{
diff --git a/src/cmd/gc/walk.c b/src/cmd/gc/walk.c
index 6029214c4e..d57dbe69d4 100644
--- a/src/cmd/gc/walk.c
+++ b/src/cmd/gc/walk.c
@@ -287,11 +287,6 @@ loop:
 		walkselect(n);
 		goto ret;
 
-	case OEMPTY:
-		if(top != Etop)
-			goto nottop;
-		goto ret;
-
 	case OIF:
 		if(top != Etop)
 			goto nottop;
@@ -500,16 +495,18 @@ loop:
 
 	case OFALL:
 	case OINDREG:
+	case OEMPTY:
 		goto ret;
 
 	case OCONV:
 		if(top == Etop)
 			goto nottop;
-		walktype(n->left, Erv);
 
 		l = n->left;
 		if(l == N)
 			goto ret;
+		walktype(l, Erv);
+
 		t = n->type;
 		if(t == T)
 			goto ret;
@@ -552,7 +549,6 @@ loop:
 		// interface and structure
 		et = isandss(n->type, l);
 		if(et != Inone) {
-if(et == I2I) dump("conv", n);
 			indir(n, ifaceop(n->type, l, et));
 			goto ret;
 		}
@@ -2980,14 +2976,10 @@ structlit(Node *n)
 
 	l = structfirst(&savel, &n->type);
 	r = listfirst(&saver, &n->left);
+	if(r != N && r->op == OEMPTY)
+		r = N;
 
 loop:
-	if(l != T && l->etype == TFIELD && l->type->etype == TFUNC) {
-		// skip methods
-		l = structnext(&savel);
-		goto loop;
-	}
-
 	if(l == T || r == N) {
 		if(l != T)
 			yyerror("struct literal expect expr of type %T", l);
@@ -3027,6 +3019,8 @@ arraylit(Node *n)
 
 		// make it a closed array
 		r = listfirst(&saver, &n->left);
+		if(r != N && r->op == OEMPTY)
+			r = N;
 		for(idx=0; r!=N; idx++)
 			r = listnext(&saver);
 		t->bound = idx;
@@ -3037,6 +3031,8 @@ arraylit(Node *n)
 
 	idx = 0;
 	r = listfirst(&saver, &n->left);
+	if(r != N && r->op == OEMPTY)
+		r = N;
 
 loop:
 	if(r == N)
@@ -3075,6 +3071,8 @@ maplit(Node *n)
 	addtop = list(addtop, a);
 
 	r = listfirst(&saver, &n->left);
+	if(r != N && r->op == OEMPTY)
+		r = N;
 
 loop:
 	if(r == N) {
-- 
2.48.1