output args declared

arguments in first block for diagnostics
thomo return
better syntax error recovery

SVN=126045

6 files changed, 113 insertions, 61 deletions

diff --git a/src/cmd/6g/gen.c b/src/cmd/6g/gen.c
index 6b4dfde80..8072b6126 100644
--- a/src/cmd/6g/gen.c
+++ b/src/cmd/6g/gen.c
@@ -106,6 +106,26 @@ allocparams(void)
 		t = funcnext(&list);
 	}
 
+	t = structfirst(&list, getoutarg(curfn->type));
+	while(t != T) {
+		if(t->nname != N && t->nname->sym->name[0] != '_') {
+			if(d == D)
+				fatal("allocparams: this nil");
+			if(d->op != ONAME) {
+				d = d->forw;
+				continue;
+			}
+
+			n = d->dnode;
+			if(n->class != PPARAM)
+				fatal("allocparams: this class");
+
+			n->xoffset = t->width;
+			d = d->forw;
+		}
+		t = structnext(&list);
+	}
+
 	/*
 	 * allocate (set xoffset) the stack
 	 * slots for all automatics.
diff --git a/src/cmd/gc/dcl.c b/src/cmd/gc/dcl.c
index 65563f3b7..0bb358069 100644
--- a/src/cmd/gc/dcl.c
+++ b/src/cmd/gc/dcl.c
@@ -353,7 +353,7 @@ funchdr(Node *n)
 		fatal("funchdr: dclcontext");
 
 	dclcontext = PAUTO;
-	markdcl("func");
+	markdcl();
 	funcargs(n->type);
 
 	if(n->type->thistuple > 0) {
@@ -368,8 +368,9 @@ funcargs(Type *t)
 {
 	Type *n1;
 	Iter save;
+	int all;
 
-	// declare the this argument
+	// declare the this/in arguments
 	n1 = funcfirst(&save, t);
 	while(n1 != T) {
 		if(n1->nname != N)
@@ -378,13 +379,22 @@ funcargs(Type *t)
 	}
 
 	// declare the outgoing arguments
-//	n1 = structfirst(&save, getoutarg(t));
-//	while(n1 != T) {
-//		n1->left = newname(n1->sym);
-//		if(n1->nname != N)
-//			addvar(n1->nname, n1->type, PPARAM);
-//		n1 = structnext(&save);
-//	}
+	all = 0;
+	n1 = structfirst(&save, getoutarg(t));
+	while(n1 != T) {
+		if(n1->nname != N && n1->nname->sym->name[0] != '_') {
+			addvar(n1->nname, n1->type, PPARAM);
+			all |= 1;
+		} else
+			all |= 2;
+		n1 = structnext(&save);
+	}
+	if(all == 3)
+		yyerror("output parameters are all named or not named");
+
+	t->outnamed = 0;
+	if(all == 1)
+		t->outnamed = 1;
 }
 
 /*
@@ -401,7 +411,7 @@ funcbody(Node *n)
 	// change the declaration context from auto to extern
 	if(dclcontext != PAUTO)
 		fatal("funcbody: dclcontext");
-	popdcl("func");
+	popdcl();
 	dclcontext = PEXTERN;
 }
 
@@ -515,7 +525,7 @@ pushdcl(Sym *s)
 }
 
 void
-popdcl(char *why)
+popdcl(void)
 {
 	Sym *d, *s;
 
@@ -532,8 +542,6 @@ popdcl(char *why)
 	}
 	if(d == S)
 		fatal("popdcl: no mark");
-	if(strcmp(why, d->package) != 0)
-		fatal("popdcl: pushed as %s popped as %s", d->package, why);
 	dclstack = d->link;
 	block = d->vblock;
 }
@@ -556,17 +564,17 @@ poptodcl(void)
 }
 
 void
-markdcl(char *why)
+markdcl(void)
 {
 	Sym *d;
 
 	d = push();
 	d->name = nil;		// used as a mark in fifo
-	d->package = why;	// diagnostic for unmatched
 	d->vblock = block;
 
 	blockgen++;
 	block = blockgen;
+
 //	if(dflag())
 //		print("markdcl\n");
 }
@@ -576,7 +584,7 @@ markdclstack(void)
 {
 	Sym *d, *s;
 
-	markdcl("fnlit");
+	markdcl();
 
 	// copy the entire pop of the stack
 	// all the way back to block0.
@@ -639,8 +647,14 @@ addvar(Node *n, Type *t, int ctxt)
 		gen = 0;
 	}
 
-	if(s->vblock == block)
-		yyerror("var %S redeclared in this block %d", s, block);
+	if(s->vblock == block) {
+		if(s->oname != N) {
+			yyerror("var %S redeclared in this block"
+				"\n     previous declaration at %L",
+				s, s->oname->lineno);
+		} else
+			yyerror("var %S redeclared in this block", s);
+	}
 		
 	if(ctxt != PEXTERN)
 		pushdcl(s);
diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index 828ebbb71..7f5b3829d 100644
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -80,6 +80,7 @@ struct	Type
 	uchar	thistuple;
 	uchar	outtuple;
 	uchar	intuple;
+	uchar	outnamed;
 
 	Sym*	sym;
 	long	vargen;		// unique name for OTYPE/ONAME
@@ -144,7 +145,7 @@ struct	Node
 	Sym*	psym;		// import
 	Sym*	sym;		// various
 	long	vargen;		// unique name for OTYPE/ONAME
-	ulong	lineno;
+	long	lineno;
 	vlong	xoffset;
 };
 #define	N	((Node*)0)
@@ -525,8 +526,8 @@ void	funcbody(Node*);
 Type*	dostruct(Node*, int);
 Type**	stotype(Node*, Type**);
 Type*	sortinter(Type*);
-void	markdcl(char*);
-void	popdcl(char*);
+void	markdcl(void);
+void	popdcl(void);
 void	poptodcl(void);
 void	markdclstack(void);
 void	testdclstack(void);
@@ -566,6 +567,7 @@ void	doimport7(Node*, Node*);
  */
 void	walk(Node*);
 void	walktype(Node*, int);
+void	walkbool(Node*);
 Type*	walkswitch(Node*, Type*(*)(Node*, Type*));
 int	casebody(Node*);
 int	whatis(Node*);
diff --git a/src/cmd/gc/go.y b/src/cmd/gc/go.y
index e3fe87a3b..67345054d 100644
--- a/src/cmd/gc/go.y
+++ b/src/cmd/gc/go.y
@@ -47,8 +47,7 @@
 %type	<node>		export_list_r export
 %type	<node>		hidden_importsym_list_r ohidden_importsym_list hidden_importsym isym
 %type	<node>		hidden_importfield_list_r ohidden_importfield_list hidden_importfield
-%type	<node>		fnbody
-%type	<node>		fnres Afnres Bfnres fnliteral xfndcl fndcl
+%type	<node>		fnres Afnres Bfnres fnliteral xfndcl fndcl fnbody
 %type	<node>		keyval_list_r keyval
 %type	<node>		typedcl Atypedcl Btypedcl
 
@@ -148,13 +147,9 @@ xdcl:
 	{
 		$$ = N;
 	}
-|	error '}'
+|	error xdcl
 	{
-		$$ = N;
-	}
-|	error ';'
-	{
-		$$ = N;
+		$$ = $2;
 	}
 
 common_dcl:
@@ -330,13 +325,12 @@ inc_stmt:
 complex_stmt:
 	LFOR for_stmt
 	{
-		/* FOR and WHILE are the same keyword */
-		popdcl("for/while");
+		popdcl();
 		$$ = $2;
 	}
 |	LSWITCH if_stmt
 	{
-		popdcl("if/switch");
+		popdcl();
 		if(!casebody($2->nbody))
 			yyerror("switch statement must have case labels");
 		$$ = $2;
@@ -346,14 +340,14 @@ complex_stmt:
 	}
 |	LIF if_stmt
 	{
-		popdcl("if/switch");
+		popdcl();
 		$$ = $2;
 		//if($$->ninit != N && $$->ntest == N)
 		//	yyerror("if conditional should not be missing");
 	}
 |	LIF if_stmt LELSE else_stmt1
 	{
-		popdcl("if/switch");
+		popdcl();
 		$$ = $2;
 		$$->nelse = $4;
 		//if($$->ninit != N && $$->ntest == N)
@@ -361,7 +355,7 @@ complex_stmt:
 	}
 |	LRANGE range_stmt
 	{
-		popdcl("range");
+		popdcl();
 		$$ = $2;
 	}
 |	LCASE expr_list ':'
@@ -414,7 +408,7 @@ semi_stmt:
 	}
 |	LIF if_stmt LELSE else_stmt2
 	{
-		popdcl("if/switch");
+		popdcl();
 		$$ = $2;
 		$$->nelse = $4;
 		//if($$->ninit != N && $$->ntest == N)
@@ -424,13 +418,13 @@ semi_stmt:
 compound_stmt:
 	'{'
 	{
-		markdcl("compound");
+		markdcl();
 	} ostmt_list '}'
 	{
 		$$ = $3;
 		if($$ == N)
 			$$ = nod(OEMPTY, N, N);
-		popdcl("compound");
+		popdcl();
 	}
 
 for_header:
@@ -460,7 +454,7 @@ for_body:
 
 for_stmt:
 	{
-		markdcl("for/while");
+		markdcl();
 	} for_body
 	{
 		$$ = $2;
@@ -491,7 +485,7 @@ if_body:
 
 if_stmt:
 	{
-		markdcl("if/switch");
+		markdcl();
 	} if_body
 	{
 		$$ = $2;
@@ -521,7 +515,7 @@ range_body:
 
 range_stmt:
 	{
-		markdcl("range");
+		markdcl();
 	} range_body
 	{
 		$$ = $2;
@@ -1012,7 +1006,7 @@ fnlitdcl:
 fnliteral:
 	fnlitdcl '{' ostmt_list '}'
 	{
-		popdcl("fnlit");
+		popdcl();
 
 		vargen++;
 		snprint(namebuf, sizeof(namebuf), "_f%.3ld", vargen);
@@ -1036,16 +1030,17 @@ fnliteral:
 	}
 
 fnbody:
-	compound_stmt
+	'{' ostmt_list '}'
 	{
-		$$ = $1;
-		if($$->op == OEMPTY)
+		$$ = $2;
+		if($$ == N)
 			$$ = nod(ORETURN, N, N);
 	}
 |	';'
 	{
 		$$ = N;
 	}
+
 fnres:
 	Afnres
 |	Bfnres
@@ -1202,11 +1197,7 @@ Astmt:
 	{
 		$$ = N;
 	}
-|	error ';'
-	{
-		$$ = N;
-	}
-|	error '}'
+|	error Astmt
 	{
 		$$ = N;
 	}
@@ -1218,6 +1209,10 @@ Astmt:
 Bstmt:
 	semi_stmt
 |	Bcommon_dcl
+|	error Bstmt
+	{
+		$$ = N;
+	}
 
 /*
  * need semi in front YES
diff --git a/src/cmd/gc/lex.c b/src/cmd/gc/lex.c
index 5aa12c328..2642bc88e 100644
--- a/src/cmd/gc/lex.c
+++ b/src/cmd/gc/lex.c
@@ -550,7 +550,7 @@ tnum:
 	}
 	*cp++ = c;
 	c = getc();
-	if(c == 'x' || c == 'X')
+	if(c == 'x' || c == 'X') {
 		for(;;) {
 			*cp++ = c;
 			c = getc();
@@ -564,16 +564,24 @@ tnum:
 				yyerror("malformed hex constant");
 			goto ncu;
 		}
-	if(c < '0' || c > '7')
-		goto dc;
+	}
+
+	c1 = 0;
 	for(;;) {
-		if(c >= '0' && c <= '7') {
-			*cp++ = c;
-			c = getc();
-			continue;
-		}
-		goto ncu;
+		if(!isdigit(c))
+			break;
+		if(c < '0' || c > '7')
+			c1 = 1;		// not octal
+		*cp++ = c;
+		c = getc();
 	}
+	if(c == '.')
+		goto casedot;
+	if(c == 'e' || c == 'E')
+		goto casee;
+	if(c1)
+		yyerror("malformed octal constant");
+	goto ncu;
 
 dc:
 	if(c == '.')
diff --git a/src/cmd/gc/walk.c b/src/cmd/gc/walk.c
index 0110fe407..f8c10c3ec 100644
--- a/src/cmd/gc/walk.c
+++ b/src/cmd/gc/walk.c
@@ -112,7 +112,7 @@ loop:
 		if(top != Etop)
 			goto nottop;
 		walktype(n->ninit, Etop);
-		walktype(n->ntest, Erv);
+		walkbool(n->ntest);
 		walktype(n->nincr, Etop);
 		n = n->nbody;
 		goto loop;
@@ -151,7 +151,7 @@ loop:
 		if(top != Etop)
 			goto nottop;
 		walktype(n->ninit, Etop);
-		walktype(n->ntest, Erv);
+		walkbool(n->ntest);
 		walktype(n->nelse, Etop);
 		n = n->nbody;
 		goto loop;
@@ -377,6 +377,10 @@ loop:
 		if(top != Etop)
 			goto nottop;
 		walktype(n->left, Erv);
+		if(curfn->type->outnamed && n->left == N) {
+			// print("special return\n");
+			goto ret;
+		}
 		l = ascompatte(n->op, getoutarg(curfn->type), &n->left, 1);
 		if(l != N)
 			n->left = reorder4(l);
@@ -722,6 +726,15 @@ ret:
 	lineno = lno;
 }
 
+void
+walkbool(Node *n)
+{
+	walktype(n, Erv);
+	if(n != N && n->type != T)
+		if(!eqtype(n->type, types[TBOOL], 0))
+			yyerror("IF and FOR require a boolean type");
+}
+
 /*
  * return the first type
  */