generate an error if the foreward

declaration of a func does not exactly
match the actual (or another foreward)
declaration. the reason is that when
there are 2 declarations of a function,
the names of the parameters are taken
from the first. thus
   func x(a int);
followed by
   func x(b int) { ... }
will have the parameter named "a" and
"b" will be undefined.

SVN=114788

src/c/dcl.c

@@ -283,6 +283,15 @@ funchdr(Node *n)
 	s = n->nname->sym;
 	on = s->oname;
 
+	// check for same types
+	if(on != N) {
+		if(eqtype(n->type, on->type, 0)) {
+			if(!eqargs(n->type, on->type))
+				yyerror("foreward declarations not the same: %S", s);
+		} else
+			yyerror("redeclare of function: %S", s);
+	}
+
 	// check for foreward declaration
 	if(on == N || !eqtype(n->type, on->type, 0)) {
 		// initial declaration or redeclaration

src/c/gen.c

@@ -87,9 +87,6 @@ loop:
 		dump("gen: unknown op", n);
 		break;
 
-	case ODCLTYPE:
-		break;
-
 	case OLIST:
 		gen(n->left);
 		n = n->right;
@@ -216,8 +213,6 @@ loop:
 		cgen_asop(n->left, n->right, n->kaka);
 		break;
 
-	case ODCLVAR:
-	case OCOLAS:
 	case OAS:
 		cgen_as(n->left, n->right, n->op, n->kaka);
 		break;
@@ -342,6 +337,19 @@ cgen(Node *n)
 		gopcode(PCONV, PTNIL, nod(OCONV, n->type, nl->type));
 		break;
 
+	case OINDEXPTRSTR:
+		nl = n->left;
+		nr = n->right;
+		if(nl->addable) {
+			cgen(nr);
+			cgen(nl);
+			gopcode(PLOADI, PTADDR, N);
+			gopcodet(PINDEXZ, nr->type, N);
+			break;
+		}
+fatal("xxx");
+		break;
+
 	case OINDEXSTR:
 		nl = n->left;
 		nr = n->right;
@@ -357,7 +365,8 @@ cgen(Node *n)
 		gopcodet(PINDEXZ, nr->type, r);
 		break;
 
-	case OSLICE:
+	case OSLICESTR:
+	case OSLICEPTRSTR:
 		nl = n->left;	// name
 		nr = n->right;
 
@@ -375,6 +384,9 @@ cgen(Node *n)
 		} else
 			gopcode(PLOAD, PTADDR, nl);
 
+		if(n->op == OSLICEPTRSTR)
+			gopcode(PLOADI, PTADDR, N);
+
 		// offset in int reg
 		cgen(nr->left);
 
@@ -806,16 +818,13 @@ loop:
 	default:
 		fatal("cgen_as: unknown op %O", op);
 
-	case ODCLVAR:
+	case OAS:
 		if(nr == N && nl->op == OLIST) {
 			kaka = PAS_SINGLE;
 			cgen_as(nl->left, nr, op, kaka);
 			nl = nl->right;
 			goto loop;
 		}
-
-	case OCOLAS:
-	case OAS:
 		switch(kaka) {
 		default:
 			yyerror("cgen_as: unknown param %d %d", kaka, PAS_CALLM);

src/c/go.h

@@ -171,12 +171,11 @@ enum
 
 	ONAME,
 	ODOT, ODOTPTR, ODOTMETH, ODOTINTER,
-	ODCLFUNC, ODCLCONST, ODCLVAR,
+	ODCLFUNC, ODCLFIELD, ODCLARG,
-	ODCLTYPE, ODCLFIELD, ODCLARG,
 	OLIST,
 	OPTR, OARRAY,
 	ORETURN, OFOR, OIF, OSWITCH,
-	OAS, OASOP, OCOLAS, OCASE, OXCASE, OFALL, OXFALL,
+	OAS, OASOP, OCASE, OXCASE, OFALL, OXFALL,
 	OGOTO, OPROC, ONEW, OPANIC, OPRINT, OEMPTY,
 
 	OOROR,
@@ -193,8 +192,9 @@ enum
 	OADDR,
 	OIND,
 	OCALL, OCALLPTR, OCALLMETH, OCALLINTER,
-	OINDEX, OINDEXPTR, OINDEXSTR, OINDEXMAP, OINDEXPTRMAP,
+	OINDEX, OINDEXSTR, OINDEXMAP,
-	OSLICE,
+	OINDEXPTR, OINDEXPTRSTR, OINDEXPTRMAP,
+	OSLICE, OSLICESTR, OSLICEPTRSTR,
 	ONOT, OCOM, OPLUS, OMINUS, OSEND, ORECV,
 	OLITERAL,
 	OCONV,
@@ -400,6 +400,7 @@ int	isptrto(Node*, int);
 int	isinter(Node*);
 int	isbytearray(Node*);
 int	eqtype(Node*, Node*, int);
+int	eqargs(Node*, Node*);
 ulong	typehash(Node*, int);
 void	frame(int);
 Node*	literal(long);

src/c/go.y

@@ -39,8 +39,6 @@
 %type	<node>		name name_name new_name new_name_list_r
 %type	<node>		type new_type
 %type	<node>		vardcl_list_r vardcl
-%type	<node>		constdcl_list_r constdcl
-%type	<node>		typedcl_list_r typedcl
 %type	<node>		interfacedcl_list_r interfacedcl
 %type	<node>		structdcl_list_r structdcl
 %type	<node>		export_list_r export
@@ -142,21 +140,21 @@ common_dcl:
 	}
 |	LCONST constdcl
 	{
-		$$ = $2;
+		$$ = N;
 		iota = 0;
 	}
 |	LCONST '(' constdcl_list_r osemi ')'
 	{
-		$$ = rev($3);
+		$$ = N;
 		iota = 0;
 	}
 |	LTYPE typedcl
 	{
-		$$ = $2;
+		$$ = N;
 	}
 |	LTYPE '(' typedcl_list_r osemi ')'
 	{
-		$$ = rev($3);
+		$$ = N;
 	}
 
 vardcl:
@@ -165,16 +163,14 @@ vardcl:
 		$$ = rev($1);
 		dodclvar($$, $2);
 
-		$$ = nod(ODCLVAR, $$, N);
+		$$ = nod(OAS, $$, N);
-		$$->type = $2;
 	}
 |	new_name_list_r type '=' oexpr_list
 	{
 		$$ = rev($1);
 		dodclvar($$, $2);
 
-		$$ = nod(ODCLVAR, $$, $4);
+		$$ = nod(OAS, $$, $4);
-		$$->type = $2;
 	}
 |	new_name '=' expr
 	{
@@ -182,8 +178,7 @@ vardcl:
 		defaultlit($3);
 		dodclvar($1, $3->type);
 
-		$$ = nod(ODCLVAR, $1, $3);
+		$$ = nod(OAS, $1, $3);
-		$$->type = $3->type;
 	}
 
 constdcl:
@@ -191,8 +186,6 @@ constdcl:
 	{
 		walktype($3, 0);
 		dodclconst($1, $3);
-
-		$$ = nod(ODCLCONST, $1, $3);
 		iota += 1;
 	}
 |	new_name type '=' expr
@@ -200,8 +193,6 @@ constdcl:
 		walktype($4, 0);
 		convlit($4, $2);
 		dodclconst($1, $4);
-
-		$$ = nod(ODCLCONST, $1, $4);
 		iota += 1;
 	}
 
@@ -209,9 +200,6 @@ typedcl:
 	new_type type
 	{
 		dodcltype($1, $2);
-
-		$$ = nod(ODCLTYPE, $1, N);
-		$$->type = $2;
 	}
 
 /*
@@ -279,7 +267,8 @@ simple_stmt:
 		walktype($3, 0);	// this is a little harry
 		defaultlit($3);
 		dodclvar($1, $3->type);
-		$$ = nod(OCOLAS, $1, $3);
+
+		$$ = nod(OAS, $1, $3);
 	}
 
 complex_stmt:
@@ -957,16 +946,10 @@ vardcl_list_r:
 constdcl_list_r:
 	constdcl
 |	constdcl_list_r ';' constdcl
-	{
-		$$ = nod(OLIST, $1, $3);
-	}
 
 typedcl_list_r:
 	typedcl
 |	typedcl_list_r ';' typedcl
-	{
-		$$ = nod(OLIST, $1, $3);
-	}
 
 structdcl_list_r:
 	structdcl

src/c/subr.c

@@ -542,16 +542,12 @@ opnames[] =
 	[OXCASE]	= "XCASE",
 	[OFALL]		= "FALL",
 	[OCONV]		= "CONV",
-	[OCOLAS]	= "COLAS",
 	[OCOM]		= "COM",
 	[OCONST]	= "CONST",
 	[OCONTINUE]	= "CONTINUE",
 	[ODCLARG]	= "DCLARG",
-	[ODCLCONST]	= "DCLCONST",
 	[ODCLFIELD]	= "DCLFIELD",
 	[ODCLFUNC]	= "DCLFUNC",
-	[ODCLTYPE]	= "DCLTYPE",
-	[ODCLVAR]	= "DCLVAR",
 	[ODIV]		= "DIV",
 	[ODOT]		= "DOT",
 	[ODOTPTR]	= "DOTPTR",
@@ -570,6 +566,7 @@ opnames[] =
 	[OINDEX]	= "INDEX",
 	[OINDEXPTR]	= "INDEXPTR",
 	[OINDEXSTR]	= "INDEXSTR",
+	[OINDEXPTRSTR]	= "INDEXPTRSTR",
 	[OINDEXMAP]	= "INDEXMAP",
 	[OINDEXPTRMAP]	= "INDEXPTRMAP",
 	[OIND]		= "IND",
@@ -597,6 +594,8 @@ opnames[] =
 	[ORETURN]	= "RETURN",
 	[ORSH]		= "RSH",
 	[OSLICE]	= "SLICE",
+	[OSLICESTR]	= "SLICESTR",
+	[OSLICEPTRSTR]	= "SLICEPTRSTR",
 	[OSUB]		= "SUB",
 	[OSWITCH]	= "SWITCH",
 	[OTYPE]		= "TYPE",
@@ -1076,8 +1075,12 @@ eqtype(Node *t1, Node *t2, int d)
 			if(t1->nname != N && t1->nname->sym != S) {
 				if(t2->nname == N || t2->nname->sym == S)
 					return 0;
-				if(strcmp(t1->nname->sym->name, t2->nname->sym->name) != 0)
+				if(strcmp(t1->nname->sym->name, t2->nname->sym->name) != 0) {
-					return 0;
+					// assigned names dont count
+					if(t1->nname->sym->name[0] != '_' ||
+				   	   t2->nname->sym->name[0] != '_')
+						return 0;
+				}
 			}
 			t1 = t1->down;
 			t2 = t2->down;
@@ -1106,6 +1109,41 @@ eqtype(Node *t1, Node *t2, int d)
 	return eqtype(t1->type, t2->type, d+1);
 }
 
+/*
+ * are the arg names of two
+ * functions the same. we know
+ * that eqtype has been called
+ * and has returned true.
+ */
+int
+eqargs(Node *t1, Node *t2)
+{
+	if(t1 == t2)
+		return 1;
+	if(t1 == N || t2 == N)
+		return 0;
+	if(t1->op != OTYPE || t2->op != OTYPE)
+		fatal("eqargs: oops %O %O", t1->op, t2->op);
+
+	if(t1->etype != t2->etype)
+		return 0;
+
+	if(t1->etype != TFUNC)
+		fatal("eqargs: oops %E", t1->etype);
+
+	t1 = t1->type;
+	t2 = t2->type;
+	for(;;) {
+		if(t1 == t2)
+			break;
+		if(!eqtype(t1, t2, 0))
+			return 0;
+		t1 = t1->down;
+		t2 = t2->down;
+	}
+	return 1;
+}
+
 ulong
 typehash(Node *at, int d)
 {

src/c/walk.c

@@ -46,9 +46,6 @@ loop:
 		fatal("walktype: switch 1 unknown op %N", n);
 		goto ret;
 
-	case ODCLTYPE:
-		goto ret;
-
 	case OPANIC:
 	case OPRINT:
 		walktype(n->left, 0);
@@ -172,8 +169,6 @@ loop:
 		ascompatte(n->op, getinarg(t), &n->right);
 		goto ret;
 
-	case OCOLAS:
-	case ODCLVAR:
 	case OAS:
 		if(!top)
 			goto nottop;
@@ -364,6 +359,13 @@ loop:
 			goto ret;
 		}
 
+		// left side is ptr to string
+		if(isptrto(t, TPTR) && isptrto(t->type, TSTRING)) {
+			n->op = OINDEXPTRSTR;
+			n->type = types[TUINT8];
+			goto ret;
+		}
+
 		// left side is array
 		if(t->etype == TPTR) {
 			t = t->type;
@@ -741,14 +743,23 @@ walkslice(Node *n)
 
 	if(n->left == N || n->right == N)
 		return;
-	walktype(n->left, 0);
-	if(!isptrto(n->left->type, TSTRING)) {
-		badtype(OSLICE, n->left->type, N);
-		return;
-	}
 	if(n->right->op != OLIST)
 		fatal("slice not a list");
 
+	walktype(n->left, 0);
+	if(isptrto(n->left->type, TSTRING)) {
+		n->op = OSLICESTR;
+		goto ok;
+	}
+	if(isptrto(n->left->type->type, TPTR) && isptrto(n->left->type->type, TSTRING)) {
+		n->op = OSLICEPTRSTR;
+		goto ok;
+	}
+
+	badtype(OSLICE, n->left->type, N);
+	return;
+
+ok:
 	// check for type errors
 	walktype(n->right, 0);
 	l = n->right->left;