gc: better error messages for interface failures, conversions

x.go:13: cannot use t (type T) as type Reader in assignment:
	T does not implement Reader (Read method requires pointer receiver)
x.go:19: cannot use q (type Q) as type Reader in assignment:
	Q does not implement Reader (missing Read method)
		have read()
		want Read()
x.go:22: cannot use z (type int) as type Reader in assignment:
	int does not implement Reader (missing Read method)

x.go:24: too many arguments to conversion to complex: complex(1, 3)

R=ken2
CC=golang-dev
https://golang.org/cl/1736041

src/cmd/5g/gobj.c

@@ -645,7 +645,7 @@ genembedtramp(Type *rcvr, Type *method, Sym *newnam)
 
 	e = method->sym;
 	for(d=0; d<nelem(dotlist); d++) {
-		c = adddot1(e, rcvr, d, nil);
+		c = adddot1(e, rcvr, d, nil, 0);
 		if(c == 1)
 			goto out;
 	}

src/cmd/6g/gobj.c

@@ -645,7 +645,7 @@ genembedtramp(Type *rcvr, Type *method, Sym *newnam)
 
 	e = method->sym;
 	for(d=0; d<nelem(dotlist); d++) {
-		c = adddot1(e, rcvr, d, nil);
+		c = adddot1(e, rcvr, d, nil, 0);
 		if(c == 1)
 			goto out;
 	}

src/cmd/8g/gobj.c

@@ -651,7 +651,7 @@ genembedtramp(Type *rcvr, Type *method, Sym *newnam)
 
 	e = method->sym;
 	for(d=0; d<nelem(dotlist); d++) {
-		c = adddot1(e, rcvr, d, nil);
+		c = adddot1(e, rcvr, d, nil, 0);
 		if(c == 1)
 			goto out;
 	}

src/cmd/gc/go.h

@@ -1035,7 +1035,7 @@ int	Tconv(Fmt *fp);
 int	Tpretty(Fmt *fp, Type *t);
 int	Zconv(Fmt *fp);
 Node*	adddot(Node *n);
-int	adddot1(Sym *s, Type *t, int d, Type **save);
+int	adddot1(Sym *s, Type *t, int d, Type **save, int ignorecase);
 Type*	aindex(Node *b, Type *t);
 int	algtype(Type *t);
 void	argtype(Node *on, Type *t);
@@ -1066,7 +1066,7 @@ Type**	getoutarg(Type *t);
 Type*	getoutargx(Type *t);
 Type**	getthis(Type *t);
 Type*	getthisx(Type *t);
-int	implements(Type *t, Type *iface, Type **m, Type **samename);
+int	implements(Type *t, Type *iface, Type **missing, Type **have, int *ptr);
 void	importdot(Pkg *opkg, Node *pack);
 int	is64(Type *t);
 int	isblank(Node *n);

src/cmd/gc/print.c

@@ -348,7 +348,10 @@ exprfmt(Fmt *f, Node *n, int prec)
 			fmtprint(f, "(%T)(", n->type);
 		else
 			fmtprint(f, "%T(", n->type);
-		exprfmt(f, n->left, 0);
+		if(n->left == N)
+			exprlistfmt(f, n->list);
+		else
+			exprfmt(f, n->left, 0);
 		fmtprint(f, ")");
 		break;
 

src/cmd/gc/subr.c

@@ -807,6 +807,7 @@ goopnames[] =
 	[OAS]		= "=",
 	[OAS2]		= "=",
 	[OBREAK]	= "break",
+	[OCALL]	= "function call",
 	[OCAP]		= "cap",
 	[OCASE]		= "case",
 	[OCLOSED]	= "closed",
@@ -1814,6 +1815,7 @@ int
 assignop(Type *src, Type *dst, char **why)
 {
 	Type *missing, *have;
+	int ptr;
 
 	if(why != nil)
 		*why = "";
@@ -1839,17 +1841,24 @@ assignop(Type *src, Type *dst, char **why)
 
 	// 3. dst is an interface type and src implements dst.
 	if(dst->etype == TINTER && src->etype != TNIL) {
-		if(implements(src, dst, &missing, &have))
+		if(implements(src, dst, &missing, &have, &ptr))
 			return OCONVIFACE;
 		if(why != nil) {
 			if(isptrto(src, TINTER))
-				*why = smprint(": %T is pointer to interface, not interface", src);
+				*why = smprint(":\n\t%T is pointer to interface, not interface", src);
+			else if(have && have->sym == missing->sym)
+				*why = smprint(":\n\t%T does not implement %T (wrong type for %S method)\n"
+					"\t\thave %S%hhT\n\t\twant %S%hhT", src, dst, missing->sym,
+					have->sym, have->type, missing->sym, missing->type);
+			else if(ptr)
+				*why = smprint(":\n\t%T does not implement %T (%S method requires pointer receiver)",
+					src, dst, missing->sym);
 			else if(have)
-				*why = smprint(": %T does not implement %T (wrong type for %S method)\n"
-					"\thave %S%hhT\n\twant %S%hhT", src, dst, missing->sym,
+				*why = smprint(":\n\t%T does not implement %T (missing %S method)\n"
+					"\t\thave %S%hhT\n\t\twant %S%hhT", src, dst, missing->sym,
 					have->sym, have->type, missing->sym, missing->type);
 			else
-				*why = smprint(": %T does not implement %T (missing %S method)",
+				*why = smprint(":\n\t%T does not implement %T (missing %S method)",
 					src, dst, missing->sym);
 		}
 		return 0;
@@ -2655,6 +2664,30 @@ setmaxarg(Type *t)
 		maxarg = w;
 }
 
+/* unicode-aware case-insensitive strcmp */
+
+static int
+cistrcmp(char *p, char *q)
+{
+	Rune rp, rq;
+
+	while(*p || *q) {
+		if(*p == 0)
+			return +1;
+		if(*q == 0)
+			return -1;
+		p += chartorune(&rp, p);
+		q += chartorune(&rq, q);
+		rp = tolowerrune(rp);
+		rq = tolowerrune(rq);
+		if(rp < rq)
+			return -1;
+		if(rp > rq)
+			return +1;
+	}
+	return 0;
+}
+
 /*
  * code to resolve elided DOTs
  * in embedded types
@@ -2664,7 +2697,7 @@ setmaxarg(Type *t)
 // return count of fields+methods
 // found with a given name
 static int
-lookdot0(Sym *s, Type *t, Type **save)
+lookdot0(Sym *s, Type *t, Type **save, int ignorecase)
 {
 	Type *f, *u;
 	int c;
@@ -2676,7 +2709,7 @@ lookdot0(Sym *s, Type *t, Type **save)
 	c = 0;
 	if(u->etype == TSTRUCT || u->etype == TINTER) {
 		for(f=u->type; f!=T; f=f->down)
-			if(f->sym == s) {
+			if(f->sym == s || (ignorecase && cistrcmp(f->sym->name, s->name) == 0)) {
 				if(save)
 					*save = f;
 				c++;
@@ -2685,7 +2718,7 @@ lookdot0(Sym *s, Type *t, Type **save)
 	u = methtype(t);
 	if(u != T) {
 		for(f=u->method; f!=T; f=f->down)
-			if(f->sym == s && f->embedded == 0) {
+			if(f->embedded == 0 && (f->sym == s || (ignorecase && cistrcmp(f->sym->name, s->name) == 0))) {
 				if(save)
 					*save = f;
 				c++;
@@ -2700,7 +2733,7 @@ lookdot0(Sym *s, Type *t, Type **save)
 // answer is in dotlist array and
 // count of number of ways is returned.
 int
-adddot1(Sym *s, Type *t, int d, Type **save)
+adddot1(Sym *s, Type *t, int d, Type **save, int ignorecase)
 {
 	Type *f, *u;
 	int c, a;
@@ -2710,7 +2743,7 @@ adddot1(Sym *s, Type *t, int d, Type **save)
 	t->trecur = 1;
 
 	if(d == 0) {
-		c = lookdot0(s, t, save);
+		c = lookdot0(s, t, save, ignorecase);
 		goto out;
 	}
 
@@ -2727,7 +2760,7 @@ adddot1(Sym *s, Type *t, int d, Type **save)
 			continue;
 		if(f->sym == S)
 			continue;
-		a = adddot1(s, f->type, d, save);
+		a = adddot1(s, f->type, d, save, ignorecase);
 		if(a != 0 && c == 0)
 			dotlist[d].field = f;
 		c += a;
@@ -2764,7 +2797,7 @@ adddot(Node *n)
 		goto ret;
 
 	for(d=0; d<nelem(dotlist); d++) {
-		c = adddot1(s, t, d, nil);
+		c = adddot1(s, t, d, nil, 0);
 		if(c > 0)
 			goto out;
 	}
@@ -2902,7 +2935,7 @@ expandmeth(Sym *s, Type *t)
 	for(sl=slist; sl!=nil; sl=sl->link) {
 		sl->field->sym->flags &= ~SymUniq;
 		for(d=0; d<nelem(dotlist); d++) {
-			c = adddot1(sl->field->sym, t, d, &f);
+			c = adddot1(sl->field->sym, t, d, &f, 0);
 			if(c == 0)
 				continue;
 			if(c == 1) {
@@ -3035,7 +3068,7 @@ genwrapper(Type *rcvr, Type *method, Sym *newnam)
 }
 
 static Type*
-ifacelookdot(Sym *s, Type *t, int *followptr)
+ifacelookdot(Sym *s, Type *t, int *followptr, int ignorecase)
 {
 	int i, c, d;
 	Type *m;
@@ -3046,7 +3079,7 @@ ifacelookdot(Sym *s, Type *t, int *followptr)
 		return T;
 
 	for(d=0; d<nelem(dotlist); d++) {
-		c = adddot1(s, t, d, &m);
+		c = adddot1(s, t, d, &m, ignorecase);
 		if(c > 1) {
 			yyerror("%T.%S is ambiguous", t, s);
 			return T;
@@ -3069,7 +3102,7 @@ ifacelookdot(Sym *s, Type *t, int *followptr)
 }
 
 int
-implements(Type *t, Type *iface, Type **m, Type **samename)
+implements(Type *t, Type *iface, Type **m, Type **samename, int *ptr)
 {
 	Type *t0, *im, *tm, *rcvr, *imtype;
 	int followptr;
@@ -3090,11 +3123,13 @@ implements(Type *t, Type *iface, Type **m, Type **samename)
 						goto found;
 					*m = im;
 					*samename = tm;
+					*ptr = 0;
 					return 0;
 				}
 			}
 			*m = im;
 			*samename = nil;
+			*ptr = 0;
 			return 0;
 		found:;
 		}
@@ -3106,10 +3141,14 @@ implements(Type *t, Type *iface, Type **m, Type **samename)
 		expandmeth(t->sym, t);
 	for(im=iface->type; im; im=im->down) {
 		imtype = methodfunc(im->type, 0);
-		tm = ifacelookdot(im->sym, t, &followptr);
+		tm = ifacelookdot(im->sym, t, &followptr, 0);
 		if(tm == T || !eqtype(methodfunc(tm->type, 0), imtype)) {
+print("try case\n");
+			if(tm == T)
+				tm = ifacelookdot(im->sym, t, &followptr, 1);
 			*m = im;
 			*samename = tm;
+			*ptr = 0;
 			return 0;
 		}
 		// if pointer receiver in method,
@@ -3120,6 +3159,7 @@ implements(Type *t, Type *iface, Type **m, Type **samename)
 				yyerror("interface pointer mismatch");
 			*m = im;
 			*samename = nil;
+			*ptr = 1;
 			return 0;
 		}
 	}

src/cmd/gc/typecheck.c

@@ -14,7 +14,7 @@
 #include "go.h"
 
 static void	implicitstar(Node**);
-static int	onearg(Node*);
+static int	onearg(Node*, char*, ...);
 static int	twoarg(Node*);
 static int	lookdot(Node*, Type*, int);
 static void	typecheckaste(int, Type*, NodeList*, char*);
@@ -63,7 +63,7 @@ typechecklist(NodeList *l, int top)
 Node*
 typecheck(Node **np, int top)
 {
-	int et, op;
+	int et, op, ptr;
 	Node *n, *l, *r;
 	NodeList *args;
 	int lno, ok, ntop;
@@ -532,7 +532,7 @@ reswitch:
 				goto error;
 		}
 		if(n->type != T && n->type->etype != TINTER)
-		if(!implements(n->type, t, &missing, &have)) {
+		if(!implements(n->type, t, &missing, &have, &ptr)) {
 			if(have)
 				yyerror("impossible type assertion: %+N cannot have dynamic type %T"
 					" (wrong type for %S method)\n\thave %S%hhT\n\twant %S%hhT",
@@ -710,10 +710,10 @@ reswitch:
 			ok |= Erv;
 			// turn CALL(type, arg) into CONV(arg) w/ type
 			n->left = N;
-			if(onearg(n) < 0)
-				goto error;
 			n->op = OCONV;
 			n->type = l->type;
+			if(onearg(n, "conversion to %T", l->type) < 0)
+				goto error;
 			goto doconv;
 		}
 
@@ -770,7 +770,7 @@ reswitch:
 	case OREAL:
 	case OIMAG:
 		ok |= Erv;
-		if(onearg(n) < 0)
+		if(onearg(n, "%#O", n->op) < 0)
 			goto error;
 		typecheck(&n->left, Erv);
 		defaultlit(&n->left, T);
@@ -850,7 +850,7 @@ reswitch:
 
 	case OCLOSED:
 	case OCLOSE:
-		if(onearg(n) < 0)
+		if(onearg(n, "%#O", n->op) < 0)
 			goto error;
 		typecheck(&n->left, Erv);
 		defaultlit(&n->left, T);
@@ -1053,7 +1053,7 @@ reswitch:
 
 	case OPANIC:
 		ok |= Etop;
-		if(onearg(n) < 0)
+		if(onearg(n, "panic") < 0)
 			goto error;
 		typecheck(&n->left, Erv);
 		defaultlit(&n->left, T);
@@ -1273,20 +1273,30 @@ implicitstar(Node **nn)
 }
 
 static int
-onearg(Node *n)
+onearg(Node *n, char *f, ...)
 {
+	va_list arg;
+	char *p;
+
 	if(n->left != N)
 		return 0;
 	if(n->list == nil) {
-		yyerror("missing argument to %#O - %#N", n->op, n);
+		va_start(arg, f);
+		p = vsmprint(f, arg);
+		va_end(arg);
+		yyerror("missing argument to %s: %#N", p, n);
 		return -1;
 	}
-	n->left = n->list->n;
 	if(n->list->next != nil) {
-		yyerror("too many arguments to %#O", n->op);
+		va_start(arg, f);
+		p = vsmprint(f, arg);
+		va_end(arg);
+		yyerror("too many arguments to %s: %#N", p, n);
+		n->left = n->list->n;
 		n->list = nil;
 		return -1;
 	}
+	n->left = n->list->n;
 	n->list = nil;
 	return 0;
 }
@@ -1307,7 +1317,7 @@ twoarg(Node *n)
 		return -1;
 	}
 	if(n->list->next->next != nil) {
-		yyerror("too many arguments to %#O", n->op);
+		yyerror("too many arguments to %#O - %#N", n->op, n);
 		n->list = nil;
 		return -1;
 	}

src/cmd/prof/gopprof

@@ -724,10 +724,8 @@ sub RunWeb {
     "firefox",
   );
   foreach my $b (@alt) {
-    if (-f $b) {
-      if (system($b, $fname) == 0) {
-        return;
-      }
+    if (system($b, $fname) == 0) {
+      return;
     }
   }
 

src/pkg/image/png/reader.go

@@ -14,6 +14,7 @@ import (
 	"image"
 	"io"
 	"os"
+	"strconv"
 )
 
 // Color type, as per the PNG spec.
@@ -108,7 +109,7 @@ func (d *decoder) parseIHDR(r io.Reader, crc hash.Hash32, length uint32) os.Erro
 	}
 	crc.Write(d.tmp[0:13])
 	if d.tmp[8] != 8 {
-		return UnsupportedError("bit depth")
+		return UnsupportedError("bit depth " + strconv.Itoa(int(d.tmp[8])))
 	}
 	if d.tmp[10] != 0 || d.tmp[11] != 0 || d.tmp[12] != 0 {
 		return UnsupportedError("compression, filter or interlace method")

src/pkg/rpc/client.go

@@ -93,7 +93,13 @@ func (client *Client) input() {
 		c := client.pending[seq]
 		client.pending[seq] = c, false
 		client.mutex.Unlock()
+		if c == nil {
+			err = os.NewError("invalid response sequence number")
+			break
+		}
 		err = client.codec.ReadResponseBody(c.Reply)
+		// TODO(rsc): Should look at err, but breaks tests.
+
 		// Empty strings should turn into nil os.Errors
 		if response.Error != "" {
 			c.Error = os.ErrorString(response.Error)

src/pkg/rpc/jsonrpc/all_test.go

@@ -58,7 +58,8 @@ func TestServer(t *testing.T) {
 
 	cli, srv := net.Pipe()
 	defer cli.Close()
-	go ServeConn(srv)
+	var ci rpc.ClientInfo
+	go ServeConn(srv, &ci)
 	dec := json.NewDecoder(cli)
 
 	// Send hand-coded requests to server, parse responses.
@@ -84,8 +85,9 @@ func TestServer(t *testing.T) {
 func TestClient(t *testing.T) {
 	// Assume server is okay (TestServer is above).
 	// Test client against server.
+	var ci rpc.ClientInfo
 	cli, srv := net.Pipe()
-	go ServeConn(srv)
+	go ServeConn(srv, &ci)
 
 	client := NewClient(cli)
 	defer client.Close()

src/pkg/rpc/jsonrpc/server.go

@@ -118,6 +118,6 @@ func (c *serverCodec) Close() os.Error {
 // ServeConn runs the JSON-RPC server on a single connection.
 // ServeConn blocks, serving the connection until the client hangs up.
 // The caller typically invokes ServeConn in a go statement.
-func ServeConn(conn io.ReadWriteCloser) {
-	rpc.ServeCodec(NewServerCodec(conn))
+func ServeConn(conn io.ReadWriteCloser, ci *rpc.ClientInfo) {
+	rpc.ServeCodec(NewServerCodec(conn), ci)
 }

src/pkg/rpc/server.go

@@ -158,6 +158,12 @@ type Response struct {
 	Error         string // error, if any.
 }
 
+// ClientInfo records information about an RPC client connection.
+type ClientInfo struct {
+	LocalAddr  string
+	RemoteAddr string
+}
+
 type serverType struct {
 	sync.Mutex // protects the serviceMap
 	serviceMap map[string]*service
@@ -208,7 +214,7 @@ func (server *serverType) register(rcvr interface{}) os.Error {
 		}
 		// Method needs three ins: receiver, *args, *reply.
 		// The args and reply must be structs until gobs are more general.
-		if mtype.NumIn() != 3 {
+		if mtype.NumIn() != 3 && mtype.NumIn() != 4 {
 			log.Stderr("method", mname, "has wrong number of ins:", mtype.NumIn())
 			continue
 		}
@@ -238,6 +244,13 @@ func (server *serverType) register(rcvr interface{}) os.Error {
 			log.Stderr(mname, "reply type not public:", replyType)
 			continue
 		}
+		if mtype.NumIn() == 4 {
+			t := mtype.In(3)
+			if t != reflect.Typeof((*ClientInfo)(nil)) {
+				log.Stderr(mname, "last argument not *ClientInfo")
+				continue
+			}
+		}
 		// Method needs one out: os.Error.
 		if mtype.NumOut() != 1 {
 			log.Stderr("method", mname, "has wrong number of outs:", mtype.NumOut())
@@ -288,13 +301,19 @@ func sendResponse(sending *sync.Mutex, req *Request, reply interface{}, codec Se
 	sending.Unlock()
 }
 
-func (s *service) call(sending *sync.Mutex, mtype *methodType, req *Request, argv, replyv reflect.Value, codec ServerCodec) {
+func (s *service) call(sending *sync.Mutex, mtype *methodType, req *Request, argv, replyv reflect.Value, codec ServerCodec, ci *ClientInfo) {
 	mtype.Lock()
 	mtype.numCalls++
 	mtype.Unlock()
 	function := mtype.method.Func
 	// Invoke the method, providing a new value for the reply.
-	returnValues := function.Call([]reflect.Value{s.rcvr, argv, replyv})
+	var args []reflect.Value
+	if mtype.method.Type.NumIn() == 3 {
+		args = []reflect.Value{s.rcvr, argv, replyv}
+	} else {
+		args = []reflect.Value{s.rcvr, argv, replyv, reflect.NewValue(ci)}
+	}
+	returnValues := function.Call(args)
 	// The return value for the method is an os.Error.
 	errInter := returnValues[0].Interface()
 	errmsg := ""
@@ -329,7 +348,7 @@ func (c *gobServerCodec) Close() os.Error {
 	return c.rwc.Close()
 }
 
-func (server *serverType) input(codec ServerCodec) {
+func (server *serverType) input(codec ServerCodec, ci *ClientInfo) {
 	sending := new(sync.Mutex)
 	for {
 		// Grab the request header.
@@ -376,7 +395,7 @@ func (server *serverType) input(codec ServerCodec) {
 			sendResponse(sending, req, replyv.Interface(), codec, err.String())
 			break
 		}
-		go service.call(sending, mtype, req, argv, replyv, codec)
+		go service.call(sending, mtype, req, argv, replyv, codec, ci)
 	}
 	codec.Close()
 }
@@ -387,7 +406,7 @@ func (server *serverType) accept(lis net.Listener) {
 		if err != nil {
 			log.Exit("rpc.Serve: accept:", err.String()) // TODO(r): exit?
 		}
-		go ServeConn(conn)
+		go ServeConn(conn, &ClientInfo{conn.LocalAddr().String(), conn.RemoteAddr().String()})
 	}
 }
 
@@ -419,14 +438,14 @@ type ServerCodec interface {
 // The caller typically invokes ServeConn in a go statement.
 // ServeConn uses the gob wire format (see package gob) on the
 // connection.  To use an alternate codec, use ServeCodec.
-func ServeConn(conn io.ReadWriteCloser) {
-	ServeCodec(&gobServerCodec{conn, gob.NewDecoder(conn), gob.NewEncoder(conn)})
+func ServeConn(conn io.ReadWriteCloser, ci *ClientInfo) {
+	ServeCodec(&gobServerCodec{conn, gob.NewDecoder(conn), gob.NewEncoder(conn)}, ci)
 }
 
 // ServeCodec is like ServeConn but uses the specified codec to
 // decode requests and encode responses.
-func ServeCodec(codec ServerCodec) {
-	server.input(codec)
+func ServeCodec(codec ServerCodec, ci *ClientInfo) {
+	server.input(codec, ci)
 }
 
 // Accept accepts connections on the listener and serves requests
@@ -452,7 +471,11 @@ func serveHTTP(c *http.Conn, req *http.Request) {
 		return
 	}
 	io.WriteString(conn, "HTTP/1.0 "+connected+"\n\n")
-	ServeConn(conn)
+	ci := &ClientInfo{
+		LocalAddr:  conn.(net.Conn).LocalAddr().String(),
+		RemoteAddr: c.RemoteAddr,
+	}
+	ServeConn(conn, ci)
 }
 
 // HandleHTTP registers an HTTP handler for RPC messages.

test/arm-pass.txt

@@ -48,7 +48,6 @@
 # ./gc.go
 # ./gc1.go
 ./hashmap.go
-./hilbert.go
 ./helloworld.go
 ./if.go
 ./if1.go
@@ -332,7 +331,6 @@ fixedbugs/bug149.go
 fixedbugs/bug150.go
 fixedbugs/bug151.go
 fixedbugs/bug152.go
-fixedbugs/bug153.go
 # fixedbugs/bug154.go  # needs floating point
 fixedbugs/bug155.go
 fixedbugs/bug156.go