add composite literal ( ) syntax.

warn about composite literal { } syntax.

R=ken
OCL=25018
CL=25023

src/cmd/gc/go.h

@@ -326,7 +326,10 @@ enum
 	OINDEX, OSLICE,
 	ONOT, OCOM, OPLUS, OMINUS, OSEND, ORECV,
 	OLITERAL, OREGISTER, OINDREG,
-	OCONV, OCOMP, OKEY, OPARAM,
+	OKEY, OPARAM,
+	OCONV,
+	OCONVDOT,
+	OCONVPAREN,
 	OBAD,
 
 	OEXTEND,	// 6g internal
@@ -805,6 +808,7 @@ void	gettype(Node*, Node*);
 void	walk(Node*);
 void	walkstate(Node*);
 void	walktype(Node*, int);
+void	walkconv(Node*);
 void	walkas(Node*);
 void	walkbool(Node*);
 Type*	walkswitch(Node*, Type*(*)(Node*, Type*));
@@ -840,8 +844,8 @@ Node*	reorder2(Node*);
 Node*	reorder3(Node*);
 Node*	reorder4(Node*);
 Node*	structlit(Node*, Node*);
-Node*	arraylit(Node*);
-Node*	maplit(Node*);
+Node*	arraylit(Node*, Node*);
+Node*	maplit(Node*, Node*);
 Node*	selectas(Node*, Node*);
 Node*	old2new(Node*, Type*);
 void	addrescapes(Node*);

src/cmd/gc/go.y

@@ -791,7 +791,7 @@ pexpr:
 	}
 |	pexpr '.' '(' type ')'
 	{
-		$$ = nod(OCONV, $1, N);
+		$$ = nod(OCONVDOT, $1, N);
 		$$->type = $4;
 	}
 |	pexpr '[' expr ']'
@@ -841,20 +841,24 @@ pexpr:
 		$$ = nod(OMAKE, $5, N);
 		$$->type = $3;
 	}
-|	latype '(' expr ')'
+|	convtype '(' braced_keyexpr_list ')'
 	{
-		$$ = nod(OCONV, $3, N);
-		$$->type = oldtype($1);
+		// typed literal
+		$$ = rev($3);
+		if($$ == N)
+			$$ = nod(OEMPTY, N, N);
+		$$ = nod(OCONVPAREN, $$, N);
+		$$->type = $1;
 	}
 |	convtype '{' braced_keyexpr_list '}'
 	{
+		if(!debug['{'])
+			warn("braces should now be parens");
 		// composite literal
 		$$ = rev($3);
 		if($$ == N)
 			$$ = nod(OEMPTY, N, N);
-		if(!iscomposite($1))
-			yyerror("illegal composite literal type %T", $1);
-		$$ = nod(OCOMP, $$, N);
+		$$ = nod(OCONVPAREN, $$, N);
 		$$->type = $1;
 	}
 |	fnliteral

src/cmd/gc/subr.c

@@ -634,9 +634,10 @@ opnames[] =
 	[OXCASE]	= "XCASE",
 	[OCMP]		= "CMP",
 	[OFALL]		= "FALL",
-	[OCONV]		= "CONV",
+	[OCONV]	= "CONV",
+	[OCONVDOT]		= "CONVDOT",
+	[OCONVPAREN]	= "CONVPAREN",
 	[OCOM]		= "COM",
-	[OCOMP]		= "COMP",
 	[OCONST]	= "CONST",
 	[OCONTINUE]	= "CONTINUE",
 	[ODCLARG]	= "DCLARG",

src/cmd/gc/walk.c

@@ -507,7 +507,7 @@ loop:
 			}
 			break;
 
-		case OCONV:
+		case OCONVDOT:
 			if(cl == 2 && cr == 1) {
 				// a,b = i.(T)
 				walktype(r->left, Erv);
@@ -590,128 +590,11 @@ loop:
 		goto ret;
 
 	case OCONV:
-		if(top == Etop)
-			goto nottop;
-
-		l = n->left;
-		if(l == N)
-			goto ret;
-
-		walktype(l, Erv);
-
-		t = n->type;
-		if(t == T)
-			goto ret;
-
-		convlit1(l, t, 1);
-
-		// nil conversion
-		if(eqtype(t, l->type, 0)) {
-			if(l->op != ONAME) {
-				indir(n, l);
-				n->type = t;
-			}
-			goto ret;
-		}
-
-		// simple fix-float
-		if(l->type != T)
-		if(isint[l->type->etype] || isfloat[l->type->etype])
-		if(isint[t->etype] || isfloat[t->etype]) {
-			evconst(n);
-			goto ret;
-		}
-
-		// to string
-		if(l->type != T)
-		if(istype(t, TSTRING)) {
-			et = l->type->etype;
-			if(isint[et]) {
-				indir(n, stringop(n, top));
-				goto ret;
-			}
-			if(et == TARRAY)
-			if(istype(l->type->type, TUINT8)) {
-				n->op = OARRAY;
-				indir(n, stringop(n, top));
-				goto ret;
-			}
-		}
-
-		// convert dynamic to static generated by ONEW/OMAKE
-		if(isfixedarray(t) && isslice(l->type))
-			goto ret;
-
-		// convert static array to dynamic array
-		if(isslice(t) && isfixedarray(l->type)) {
-			if(eqtype(t->type->type, l->type->type->type, 0)) {
-				indir(n, arrayop(n, Erv));
-				goto ret;
-			}
-		}
-
-		// interface assignment
-		et = ifaceas(n->type, l->type, 1);
-		if(et != Inone) {
-			indir(n, ifaceop(n->type, l, et));
-			goto ret;
-		}
-
-		// convert to unsafe.pointer
-		if(isptrto(n->type, TANY)) {
-			if(isptr[l->type->etype])
-				goto ret;
-			if(l->type->etype == TUINTPTR)
-				goto ret;
-		}
-
-		// convert from unsafe.pointer
-		if(isptrto(l->type, TANY)) {
-			if(isptr[n->type->etype])
-				goto ret;
-			if(n->type->etype == TUINTPTR)
-				goto ret;
-		}
-
-		if(l->type != T)
-			yyerror("cannot convert %T to %T", l->type, t);
-		goto ret;
-
-	case OCOMP:
-		if(top == Etop)
+	case OCONVDOT:
+	case OCONVPAREN:
+		if(top != Erv)
 			goto nottop;
-
-		l = n->left;
-		if(l == N)
-			goto ret;
-
-		walktype(l, Erv);
-
-		t = n->type;
-		if(t == T)
-			goto ret;
-
-		// structure literal
-		if(t->etype == TSTRUCT) {
-			indir(n, structlit(n, nil));
-			goto ret;
-		}
-
-		// array literal
-		if(t->etype == TARRAY) {
-			r = arraylit(n);
-			indir(n, r);
-			goto ret;
-		}
-
-		// map literal
-		if(t->etype == TMAP) {
-			r = maplit(n);
-			indir(n, r);
-			goto ret;
-		}
-
-		yyerror("bad composite literal %T", t);
+		walkconv(n);
 		goto ret;
 
 	case ORETURN:
@@ -1001,14 +884,18 @@ loop:
 	case OADDR:
 		if(top != Erv)
 			goto nottop;
-		if(n->left->op == OCOMP && n->left->type != T)
-		if(n->left->type->etype == TSTRUCT) {
-			// turn &Point{1, 2} into allocation.
+		if(n->left->op == OCONVPAREN && n->left->type != T)
+		switch(n->left->type->etype) {
+		case TSTRUCT:
+		case TARRAY:
+		case TMAP:
+			// turn &Point(1, 2) or &[]int(1, 2) or &[...]int(1, 2) into allocation.
 			// initialize with
 			//	nvar := new(*Point);
-			//	*nvar = Point{1, 2};
+			//	*nvar = Point(1, 2);
 			// and replace expression with nvar
-			Node *nvar, *nas;
+			; // stupid c syntax - case label must be on stmt, not decl
+			Node *nvar, *nas, *nstar;
 
 			nvar = nod(OXXX, N, N);
 			tempname(nvar, ptrto(n->left->type));
@@ -1016,10 +903,27 @@ loop:
 			nas = nod(OAS, nvar, callnew(n->left->type));
 			addtop = list(addtop, nas);
 
-			structlit(n->left, nvar);
+			nstar = nod(OIND, nvar, N);
+			nstar->type = n->left->type;
+
+			switch(n->left->type->etype) {
+			case TSTRUCT:
+				structlit(n->left, nstar);
+				break;
+			case TARRAY:
+				arraylit(n->left, nstar);
+				break;
+			case TMAP:
+				maplit(n->left, nstar);
+				break;
+			default:
+				fatal("addr lit %T", n->left->type);
+			}
+
 			indir(n, nvar);
 			goto ret;
 		}
+
 		if(istype(n->left->type, TFUNC) && n->left->class == PFUNC) {
 			if(!n->diag) {
 				n->diag = 1;
@@ -1223,6 +1127,133 @@ walkbool(Node *n)
 			yyerror("IF and FOR require a boolean type");
 }
 
+void
+walkconv(Node *n)
+{
+	int et, op;
+	Type *t;
+	Node *l;
+
+	t = n->type;
+	if(t == T)
+		return;
+	l = n->left;
+	if(l == N)
+		return;
+	walktype(l, Erv);
+
+	switch(t->etype) {
+	case TSTRUCT:
+	case TMAP:
+	case TARRAY:
+		break;
+	default:
+		convlit1(l, t, 1);
+	}
+
+	op = n->op;
+	n->op = OCONV;	// generic conversion
+
+	// nil conversion
+	if(eqtype(t, l->type, 0)) {
+		if(l->op != ONAME) {
+			indir(n, l);
+			n->type = t;
+		}
+		return;
+	}
+
+	// simple fix-float
+	if(l->type != T)
+	if(isint[l->type->etype] || isfloat[l->type->etype])
+	if(isint[t->etype] || isfloat[t->etype]) {
+		evconst(n);
+		return;
+	}
+
+	// to string
+	if(l->type != T)
+	if(istype(t, TSTRING)) {
+		et = l->type->etype;
+		if(isint[et]) {
+			indir(n, stringop(n, Erv));
+			return;
+		}
+		if(et == TARRAY)
+		if(istype(l->type->type, TUINT8)) {
+			n->op = OARRAY;
+			indir(n, stringop(n, Erv));
+			return;
+		}
+	}
+
+	// convert dynamic to static generated by ONEW/OMAKE
+	if(isfixedarray(t) && isslice(l->type))
+		return;
+
+	// convert static array to dynamic array
+	if(isslice(t) && isfixedarray(l->type)) {
+		if(eqtype(t->type->type, l->type->type->type, 0)) {
+			indir(n, arrayop(n, Erv));
+			return;
+		}
+	}
+
+	// convert to unsafe.pointer
+	if(isptrto(n->type, TANY)) {
+		if(isptr[l->type->etype])
+			return;
+		if(l->type->etype == TUINTPTR)
+			return;
+	}
+
+	// convert from unsafe.pointer
+	if(isptrto(l->type, TANY)) {
+		if(isptr[n->type->etype])
+			return;
+		if(n->type->etype == TUINTPTR)
+			return;
+	}
+
+	// possible interface conversion if using .(T)
+	if(op == OCONVDOT) {
+		// interface conversion
+		et = ifaceas(n->type, l->type, 1);
+		if(et != Inone) {
+			indir(n, ifaceop(n->type, l, et));
+			return;
+		}
+	}
+
+	// possible composite literal if using T()
+	if(op == OCONVPAREN) {
+		// structure literal
+		if(t->etype == TSTRUCT) {
+			indir(n, structlit(n, N));
+			return;
+		}
+
+		// array literal
+		if(t->etype == TARRAY) {
+			indir(n, arraylit(n, N));
+			return;
+		}
+
+		// map literal
+		if(t->etype == TMAP) {
+			indir(n, maplit(n, N));
+			return;
+		}
+	}
+
+	if(l->type != T)
+		yyerror("invalid conversion: %T to %T", l->type, t);
+	else if(n->left->op == OLIST)
+		yyerror("invalid type for composite literal: %T", t);
+}
+
+
+
 /*
  * return the first type
  */
@@ -3110,7 +3141,7 @@ multi:
 		n = list(n, a);
 		break;
 
-	case OCONV:
+	case OCONVDOT:
 		// a,b := i.(T)
 		if(cl != 2)
 			goto badt;
@@ -3538,11 +3569,11 @@ loop:
 }
 
 Node*
-arraylit(Node *n)
+arraylit(Node *n, Node *var)
 {
 	Iter saver;
 	Type *t;
-	Node *var, *r, *a, *nnew;
+	Node *r, *a, *nnew;
 	int idx, ninit, b;
 
 	t = n->type;
@@ -3567,8 +3598,10 @@ arraylit(Node *n)
 		t->bound = b;
 	}
 
-	var = nod(OXXX, N, N);
-	tempname(var, t);
+	if(var == N) {
+		var = nod(OXXX, N, N);
+		tempname(var, t);
+	}
 
 	nnew = nil;
 	if(b < 0) {
@@ -3606,18 +3639,20 @@ arraylit(Node *n)
 }
 
 Node*
-maplit(Node *n)
+maplit(Node *n, Node *var)
 {
 	Iter saver;
 	Type *t;
-	Node *var, *r, *a;
+	Node *r, *a;
 
 	t = n->type;
 	if(t->etype != TMAP)
 		fatal("maplit: not map");
 
-	var = nod(OXXX, N, N);
-	tempname(var, t);
+	if(var == N) {
+		var = nod(OXXX, N, N);
+		tempname(var, t);
+	}
 
 	a = nod(OMAKE, N, N);
 	a->type = t;