diff --git a/bind/gen.go b/bind/gen.go
index beef4b473..0bc839fd2 100644
--- a/bind/gen.go
+++ b/bind/gen.go
@@ -43,6 +43,10 @@ const (
 	modeRetained
 )
 
+type Reporter interface {
+	Message(s string)
+}
+
 func (list ErrorList) Error() string {
 	buf := new(bytes.Buffer)
 	for i, err := range list {
@@ -85,6 +89,8 @@ type Generator struct {
 	Pkg    *types.Package
 	err    ErrorList
 
+	Reporter Reporter
+
 	// fields set by init.
 	pkgName   string
 	pkgPrefix string
diff --git a/bind/gengo.go b/bind/gengo.go
index 82aa4fc0c..18da604b7 100644
--- a/bind/gengo.go
+++ b/bind/gengo.go
@@ -7,6 +7,7 @@ package bind
 import (
 	"bytes"
 	"fmt"
+	"go/token"
 	"go/types"
 	"strings"
 )
@@ -189,7 +190,7 @@ func (g *goGen) paramName(params *types.Tuple, pos int) string {
 
 func (g *goGen) genFunc(o *types.Func) {
 	if !g.isSigSupported(o.Type()) {
-		g.Printf("// skipped function %s with unsupported parameter or result types\n", o.Name())
+		g.warnf(o.Pos(), "skipped function %s with unsupported parameter or result types", o.Name())
 		return
 	}
 	g.genFuncSignature(o, "")
@@ -205,7 +206,7 @@ func (g *goGen) genStruct(obj *types.TypeName, T *types.Struct) {
 
 	for _, f := range fields {
 		if t := f.Type(); !g.isSupported(t) {
-			g.Printf("// skipped field %s.%s with unsupported type: %s\n\n", obj.Name(), f.Name(), t)
+			g.warnf(f.Pos(), "skipped field %s.%s with unsupported type: %s", obj.Name(), f.Name(), t)
 			continue
 		}
 		g.Printf("//export proxy%s_%s_%s_Set\n", g.pkgPrefix, obj.Name(), f.Name())
@@ -230,7 +231,7 @@ func (g *goGen) genStruct(obj *types.TypeName, T *types.Struct) {
 
 	for _, m := range methods {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", obj.Name(), m.Name())
 			continue
 		}
 		g.genFuncSignature(m, obj.Name())
@@ -252,7 +253,7 @@ func (g *goGen) genStruct(obj *types.TypeName, T *types.Struct) {
 
 func (g *goGen) genVar(o *types.Var) {
 	if t := o.Type(); !g.isSupported(t) {
-		g.Printf("// skipped variable %s with unsupported type %s\n\n", o.Name(), t)
+		g.warnf(o.Pos(), "skipped variable %s with unsupported type %s", o.Name(), t)
 		return
 	}
 	// TODO(hyangah): non-struct pointer types (*int), struct type.
@@ -289,7 +290,7 @@ func (g *goGen) genInterface(obj *types.TypeName) {
 	// Define the entry points.
 	for _, m := range summary.callable {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", obj.Name(), m.Name())
 			continue
 		}
 		g.genFuncSignature(m, obj.Name())
@@ -318,7 +319,7 @@ func (g *goGen) genInterface(obj *types.TypeName) {
 
 	for _, m := range summary.callable {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or result types\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or result types", obj.Name(), m.Name())
 			continue
 		}
 		sig := m.Type().(*types.Signature)
@@ -591,3 +592,11 @@ func (g *goGen) pkgName(pkg *types.Package) string {
 	g.importMap[pkg] = name
 	return name + "."
 }
+
+func (g *goGen) warnf(pos token.Pos, format string, args ...interface{}) {
+	if g.Reporter != nil {
+		fpos := g.Fset.Position(pos)
+		g.Reporter.Message(fmt.Sprintf(fpos.String()+": "+format, args...))
+	}
+	g.Printf("// "+format+"\n\n", args...)
+}
diff --git a/bind/genjava.go b/bind/genjava.go
index e31bebaae..3fb508762 100644
--- a/bind/genjava.go
+++ b/bind/genjava.go
@@ -7,6 +7,7 @@ package bind
 import (
 	"fmt"
 	"go/constant"
+	"go/token"
 	"go/types"
 	"html"
 	"math"
@@ -295,7 +296,7 @@ func (g *JavaGen) genStruct(s structInfo) {
 	cons := g.constructors[s.obj]
 	for _, f := range cons {
 		if !g.isConsSigSupported(f.Type()) {
-			g.Printf("// skipped constructor %s.%s with unsupported parameter or return types\n\n", n, f.Name())
+			g.warnf(f.Pos(), "skipped constructor %s.%s with unsupported parameter or return types", n, f.Name())
 			continue
 		}
 		g.genConstructor(f, n, jinf != nil)
@@ -312,7 +313,7 @@ func (g *JavaGen) genStruct(s structInfo) {
 
 	for _, f := range fields {
 		if t := f.Type(); !g.isSupported(t) {
-			g.Printf("// skipped field %s.%s with unsupported type: %s\n\n", n, f.Name(), t)
+			g.warnf(f.Pos(), "skipped field %s.%s with unsupported type: %s", n, f.Name(), t)
 			continue
 		}
 
@@ -326,7 +327,7 @@ func (g *JavaGen) genStruct(s structInfo) {
 	var isStringer bool
 	for _, m := range methods {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", n, m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", n, m.Name())
 			continue
 		}
 		g.javadoc(doc.Member(m.Name()))
@@ -487,7 +488,7 @@ func (g *JavaGen) genObjectMethods(n string, fields []*types.Var, isStringer boo
 	g.Printf("%s that = (%s)o;\n", n, n)
 	for _, f := range fields {
 		if t := f.Type(); !g.isSupported(t) {
-			g.Printf("// skipped field %s.%s with unsupported type: %s\n\n", n, f.Name(), t)
+			g.warnf(f.Pos(), "skipped field %s.%s with unsupported type: %s", n, f.Name(), t)
 			continue
 		}
 		nf := f.Name()
@@ -581,7 +582,7 @@ func (g *JavaGen) genInterface(iface interfaceInfo) {
 
 	for _, m := range iface.summary.callable {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", iface.obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", iface.obj.Name(), m.Name())
 			continue
 		}
 		g.javadoc(doc.Member(m.Name()))
@@ -862,7 +863,7 @@ func (g *JavaGen) genFuncSignature(o *types.Func, jm *java.Func, hasThis bool) {
 
 func (g *JavaGen) genVar(o *types.Var) {
 	if t := o.Type(); !g.isSupported(t) {
-		g.Printf("// skipped variable %s with unsupported type: %s\n\n", o.Name(), t)
+		g.warnf(o.Pos(), "skipped variable %s with unsupported type: %s", o.Name(), t)
 		return
 	}
 	jType := g.javaType(o.Type())
@@ -1043,7 +1044,7 @@ func JavaClassName(pkg *types.Package) string {
 
 func (g *JavaGen) genConst(o *types.Const) {
 	if _, ok := o.Type().(*types.Basic); !ok || !g.isSupported(o.Type()) {
-		g.Printf("// skipped const %s with unsupported type: %s\n\n", o.Name(), o.Type())
+		g.warnf(o.Pos(), "skipped const %s with unsupported type: %s", o.Name(), o.Type())
 		return
 	}
 	// TODO(hyangah): should const names use upper cases + "_"?
@@ -1077,7 +1078,7 @@ func (g *JavaGen) genConst(o *types.Const) {
 
 func (g *JavaGen) genJNIField(o *types.TypeName, f *types.Var) {
 	if t := f.Type(); !g.isSupported(t) {
-		g.Printf("// skipped field %s with unsupported type: %s\n\n", o.Name(), t)
+		g.warnf(f.Pos(), "skipped field %s with unsupported type: %s", o.Name(), t)
 		return
 	}
 	n := java.JNIMangle(g.javaTypeName(o.Name()))
@@ -1107,7 +1108,7 @@ func (g *JavaGen) genJNIField(o *types.TypeName, f *types.Var) {
 
 func (g *JavaGen) genJNIVar(o *types.Var) {
 	if t := o.Type(); !g.isSupported(t) {
-		g.Printf("// skipped variable %s with unsupported type: %s\n\n", o.Name(), t)
+		g.warnf(o.Pos(), "skipped variable %s with unsupported type: %s", o.Name(), t)
 		return
 	}
 	n := java.JNIMangle(g.javaTypeName(o.Name()))
@@ -1187,7 +1188,7 @@ func (g *JavaGen) genJNIFunc(o *types.Func, sName string, jm *java.Func, proxy,
 		if sName != "" {
 			n = sName + "." + n
 		}
-		g.Printf("// skipped function %s with unsupported parameter or return types\n\n", n)
+		g.warnf(o.Pos(), "skipped function %s with unsupported parameter or return types", n)
 		return
 	}
 	g.genJNIFuncSignature(o, sName, jm, proxy, isjava)
@@ -1276,7 +1277,7 @@ func (g *JavaGen) genRelease(varName string, t types.Type, mode varMode) {
 
 func (g *JavaGen) genMethodInterfaceProxy(oName string, m *types.Func) {
 	if !g.isSigSupported(m.Type()) {
-		g.Printf("// skipped method %s with unsupported parameter or return types\n\n", oName)
+		g.warnf(m.Pos(), "skipped method %s with unsupported parameter or return types", oName)
 		return
 	}
 	sig := m.Type().(*types.Signature)
@@ -1345,7 +1346,7 @@ func (g *JavaGen) GenH() error {
 		g.Printf("\n")
 		for _, m := range iface.summary.callable {
 			if !g.isSigSupported(m.Type()) {
-				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", iface.obj.Name(), m.Name())
+				g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", iface.obj.Name(), m.Name())
 				continue
 			}
 			g.genInterfaceMethodSignature(m, iface.obj.Name(), true, g.paramName)
@@ -1477,7 +1478,7 @@ func (g *JavaGen) GenC() error {
 		g.Printf("jmethodID proxy_class_%s_%s_cons;\n", g.pkgPrefix, iface.obj.Name())
 		for _, m := range iface.summary.callable {
 			if !g.isSigSupported(m.Type()) {
-				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", iface.obj.Name(), m.Name())
+				g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", iface.obj.Name(), m.Name())
 				continue
 			}
 			g.Printf("static jmethodID mid_%s_%s;\n", iface.obj.Name(), m.Name())
@@ -1519,7 +1520,7 @@ func (g *JavaGen) GenC() error {
 		g.Printf("clazz = (*env)->FindClass(env, %q);\n", g.jniClassSigPrefix(pkg)+g.javaTypeName(iface.obj.Name()))
 		for _, m := range iface.summary.callable {
 			if !g.isSigSupported(m.Type()) {
-				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", iface.obj.Name(), m.Name())
+				g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", iface.obj.Name(), m.Name())
 				continue
 			}
 			sig := m.Type().(*types.Signature)
@@ -1630,7 +1631,7 @@ func (g *JavaGen) GenJava() error {
 		}
 		for _, m := range iface.summary.callable {
 			if !g.isSigSupported(m.Type()) {
-				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", n, m.Name())
+				g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", n, m.Name())
 				continue
 			}
 			g.Printf("public native ")
@@ -1652,7 +1653,7 @@ func (g *JavaGen) GenJava() error {
 	}
 	for _, f := range g.funcs {
 		if !g.isSigSupported(f.Type()) {
-			g.Printf("// skipped function %s with unsupported parameter or return types\n\n", f.Name())
+			g.warnf(f.Pos(), "skipped function %s with unsupported parameter or return types", f.Name())
 			continue
 		}
 		g.javadoc(g.docs[f.Name()].Doc())
@@ -1669,6 +1670,14 @@ func (g *JavaGen) GenJava() error {
 	return nil
 }
 
+func (g *JavaGen) warnf(pos token.Pos, format string, args ...interface{}) {
+	if g.Reporter != nil {
+		fpos := g.Fset.Position(pos)
+		g.Reporter.Message(fmt.Sprintf(fpos.String()+": "+format, args...))
+	}
+	g.Printf("// "+format+"\n\n", args...)
+}
+
 // embeddedJavaClasses returns the possible empty list of Java types embedded
 // in the given struct type.
 func embeddedJavaClasses(t *types.Struct) []string {
diff --git a/bind/genobjc.go b/bind/genobjc.go
index 7595fa0ff..1188975f3 100644
--- a/bind/genobjc.go
+++ b/bind/genobjc.go
@@ -7,6 +7,7 @@ package bind
 import (
 	"fmt"
 	"go/constant"
+	"go/token"
 	"go/types"
 	"math"
 	"strings"
@@ -121,7 +122,7 @@ func (g *ObjcGen) GenGoH() error {
 		}
 		for _, m := range i.summary.callable {
 			if !g.isSigSupported(m.Type()) {
-				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", i.obj.Name(), m.Name())
+				g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", i.obj.Name(), m.Name())
 				continue
 			}
 			g.genInterfaceMethodSignature(m, i.obj.Name(), true, g.paramName)
@@ -192,7 +193,7 @@ func (g *ObjcGen) GenH() error {
 	// TODO: prefix with k?, or use a class method?
 	for _, obj := range g.constants {
 		if _, ok := obj.Type().(*types.Basic); !ok || !g.isSupported(obj.Type()) {
-			g.Printf("// skipped const %s with unsupported type: %s\n\n", obj.Name(), obj.Type())
+			g.warnf(obj.Pos(), "skipped const %s with unsupported type: %s", obj.Name(), obj.Type())
 			continue
 		}
 		g.objcdoc(g.docs[obj.Name()].Doc())
@@ -212,7 +213,7 @@ func (g *ObjcGen) GenH() error {
 		g.Printf("@interface %s : NSObject\n", g.namePrefix)
 		for _, obj := range g.vars {
 			if t := obj.Type(); !g.isSupported(t) {
-				g.Printf("// skipped variable %s with unsupported type: %s\n\n", obj.Name(), t)
+				g.warnf(obj.Pos(), "skipped variable %s with unsupported type: %s", obj.Name(), t)
 				continue
 			}
 			objcType := g.objcType(obj.Type())
@@ -307,7 +308,7 @@ func (g *ObjcGen) GenM() error {
 
 	for _, obj := range g.funcs {
 		if !g.isSigSupported(obj.Type()) {
-			g.Printf("// skipped function %s with unsupported parameter or return types\n\n", obj.Name())
+			g.warnf(obj.Pos(), "skipped function %s with unsupported parameter or return types", obj.Name())
 			continue
 		}
 		g.genFuncM(obj)
@@ -317,7 +318,7 @@ func (g *ObjcGen) GenM() error {
 	for _, i := range g.interfaces {
 		for _, m := range i.summary.callable {
 			if !g.isSigSupported(m.Type()) {
-				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", i.obj.Name(), m.Name())
+				g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", i.obj.Name(), m.Name())
 				continue
 			}
 			g.genInterfaceMethodProxy(i.obj, m)
@@ -339,7 +340,7 @@ func (g *ObjcGen) GenM() error {
 
 func (g *ObjcGen) genVarM(o *types.Var) {
 	if t := o.Type(); !g.isSupported(t) {
-		g.Printf("// skipped variable %s with unsupported type: %s\n\n", o.Name(), t)
+		g.warnf(o.Pos(), "skipped variable %s with unsupported type: %s", o.Name(), t)
 		return
 	}
 	objcType := g.objcType(o.Type())
@@ -366,7 +367,7 @@ func (g *ObjcGen) genVarM(o *types.Var) {
 
 func (g *ObjcGen) genConstM(o *types.Const) {
 	if _, ok := o.Type().(*types.Basic); !ok || !g.isSupported(o.Type()) {
-		g.Printf("// skipped const %s with unsupported type: %s\n\n", o.Name(), o.Type())
+		g.warnf(o.Pos(), "skipped const %s with unsupported type: %s", o.Name(), o.Type())
 		return
 	}
 	cName := fmt.Sprintf("%s%s", g.namePrefix, o.Name())
@@ -631,7 +632,7 @@ func (g *ObjcGen) paramName(params *types.Tuple, pos int) string {
 
 func (g *ObjcGen) genFuncH(obj *types.Func) {
 	if !g.isSigSupported(obj.Type()) {
-		g.Printf("// skipped function %s with unsupported parameter or return types\n\n", obj.Name())
+		g.warnf(obj.Pos(), "skipped function %s with unsupported parameter or return types", obj.Name())
 		return
 	}
 	if s := g.funcSummary(nil, obj); s != nil {
@@ -883,7 +884,7 @@ func (g *ObjcGen) genInterfaceInterface(obj *types.TypeName, summary ifaceSummar
 	g.Printf("- (nonnull instancetype)initWithRef:(_Nonnull id)ref;\n")
 	for _, m := range summary.callable {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", obj.Name(), m.Name())
 			continue
 		}
 		s := g.funcSummary(nil, m)
@@ -902,7 +903,7 @@ func (g *ObjcGen) genInterfaceH(obj *types.TypeName, t *types.Interface) {
 	g.Printf("@protocol %s%s <NSObject>\n", g.namePrefix, obj.Name())
 	for _, m := range makeIfaceSummary(t).callable {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", obj.Name(), m.Name())
 			continue
 		}
 		s := g.funcSummary(nil, m)
@@ -936,7 +937,7 @@ func (g *ObjcGen) genInterfaceM(obj *types.TypeName, t *types.Interface) bool {
 
 	for _, m := range summary.callable {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", obj.Name(), m.Name())
 			continue
 		}
 		s := g.funcSummary(nil, m)
@@ -1104,7 +1105,7 @@ func (g *ObjcGen) genStructH(obj *types.TypeName, t *types.Struct) {
 	if oinf == nil {
 		for _, f := range cons {
 			if !g.isSigSupported(f.Type()) {
-				g.Printf("// skipped constructor %s.%s with unsupported parameter or return types\n\n", obj.Name(), f.Name())
+				g.warnf(f.Pos(), "skipped constructor %s.%s with unsupported parameter or return types", obj.Name(), f.Name())
 				continue
 			}
 			g.genInitH(obj, f)
@@ -1118,7 +1119,7 @@ func (g *ObjcGen) genStructH(obj *types.TypeName, t *types.Struct) {
 	// accessors to exported fields.
 	for _, f := range exportedFields(t) {
 		if t := f.Type(); !g.isSupported(t) {
-			g.Printf("// skipped field %s.%s with unsupported type: %s\n\n", obj.Name(), f.Name(), t)
+			g.warnf(f.Pos(), "skipped field %s.%s with unsupported type: %s", obj.Name(), f.Name(), t)
 			continue
 		}
 		name, typ := f.Name(), g.objcType(f.Type())
@@ -1131,7 +1132,7 @@ func (g *ObjcGen) genStructH(obj *types.TypeName, t *types.Struct) {
 	// exported methods
 	for _, m := range exportedMethodSet(types.NewPointer(obj.Type())) {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", obj.Name(), m.Name())
 			continue
 		}
 		s := g.funcSummary(obj, m)
@@ -1167,7 +1168,7 @@ func (g *ObjcGen) genStructM(obj *types.TypeName, t *types.Struct) {
 	if oinf == nil {
 		for _, f := range cons {
 			if !g.isSigSupported(f.Type()) {
-				g.Printf("// skipped constructor %s.%s with unsupported parameter or return types\n\n", obj, f.Name())
+				g.warnf(f.Pos(), "skipped constructor %s.%s with unsupported parameter or return types", obj, f.Name())
 				continue
 			}
 			g.genInitM(obj, f)
@@ -1189,7 +1190,7 @@ func (g *ObjcGen) genStructM(obj *types.TypeName, t *types.Struct) {
 
 	for _, f := range fields {
 		if !g.isSupported(f.Type()) {
-			g.Printf("// skipped unsupported field %s with type %s\n\n", f.Name(), f.Type())
+			g.warnf(f.Pos(), "skipped unsupported field %s with type %s", f.Name(), f.Type())
 			continue
 		}
 		g.genGetter(obj.Name(), f)
@@ -1198,7 +1199,7 @@ func (g *ObjcGen) genStructM(obj *types.TypeName, t *types.Struct) {
 
 	for _, m := range methods {
 		if !g.isSigSupported(m.Type()) {
-			g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", obj.Name(), m.Name())
+			g.warnf(m.Pos(), "skipped method %s.%s with unsupported parameter or return types", obj.Name(), m.Name())
 			continue
 		}
 		s := g.funcSummary(obj, m)
@@ -1260,6 +1261,14 @@ func (g *ObjcGen) genInitM(obj *types.TypeName, f *types.Func) {
 	g.Printf("}\n\n")
 }
 
+func (g *ObjcGen) warnf(pos token.Pos, format string, args ...interface{}) {
+	if g.Reporter != nil {
+		fpos := g.Fset.Position(pos)
+		g.Reporter.Message(fmt.Sprintf(fpos.String()+": "+format, args...))
+	}
+	g.Printf("// "+format+"\n\n", args...)
+}
+
 func (g *ObjcGen) errorf(format string, args ...interface{}) {
 	g.err = append(g.err, fmt.Errorf(format, args...))
 }
diff --git a/bind/testdata/ignore.go.golden b/bind/testdata/ignore.go.golden
index 486db372c..0474724df 100644
--- a/bind/testdata/ignore.go.golden
+++ b/bind/testdata/ignore.go.golden
@@ -44,7 +44,9 @@ func (p *proxyignore_I) Bind_proxy_refnum__() int32 {
 }
 
 // skipped method I.Argument with unsupported parameter or result types
+
 // skipped method I.Result with unsupported parameter or result types
+
 // skipped variable C128 with unsupported type complex128
 
 // skipped variable C64 with unsupported type complex64
@@ -60,4 +62,5 @@ func (p *proxyignore_I) Bind_proxy_refnum__() int32 {
 // skipped variable Var with unsupported type interface{}
 
 // skipped function Argument with unsupported parameter or result types
+
 // skipped function Result with unsupported parameter or result types
diff --git a/cmd/gobind/gen.go b/cmd/gobind/gen.go
index ce2bc5d22..c725c8db3 100644
--- a/cmd/gobind/gen.go
+++ b/cmd/gobind/gen.go
@@ -25,7 +25,21 @@ import (
 	"golang.org/x/tools/go/packages"
 )
 
-func genPkg(lang string, p *types.Package, astFiles []*ast.File, allPkg []*types.Package, classes []*java.Class, otypes []*objc.Named) {
+type consoleReporter struct {
+	msgs []string
+}
+
+func (r *consoleReporter) Message(s string) {
+	r.msgs = append(r.msgs, s)
+}
+
+func (r *consoleReporter) PrintMessages() {
+	if len(r.msgs) > 0 {
+		fmt.Fprintln(os.Stderr, strings.Join(r.msgs, "\n"))
+	}
+}
+
+func genPkg(lang string, fset *token.FileSet, p *types.Package, astFiles []*ast.File, allPkg []*types.Package, classes []*java.Class, otypes []*objc.Named) {
 	fname := defaultFileName(lang, p)
 	conf := &bind.GeneratorConfig{
 		Fset:   fset,
@@ -39,12 +53,14 @@ func genPkg(lang string, p *types.Package, astFiles []*ast.File, allPkg []*types
 		pname = "universe"
 	}
 	var buf bytes.Buffer
+	var reporter consoleReporter
 	generator := &bind.Generator{
-		Printer: &bind.Printer{Buf: &buf, IndentEach: []byte("\t")},
-		Fset:    conf.Fset,
-		AllPkg:  conf.AllPkg,
-		Pkg:     conf.Pkg,
-		Files:   astFiles,
+		Printer:  &bind.Printer{Buf: &buf, IndentEach: []byte("\t")},
+		Fset:     conf.Fset,
+		AllPkg:   conf.AllPkg,
+		Pkg:      conf.Pkg,
+		Files:    astFiles,
+		Reporter: &reporter,
 	}
 	switch lang {
 	case "java":
@@ -169,6 +185,7 @@ func genPkg(lang string, p *types.Package, astFiles []*ast.File, allPkg []*types
 	default:
 		errorf("unknown target language: %q", lang)
 	}
+	reporter.PrintMessages()
 }
 
 func genPkgH(w io.Writer, pname string) {
@@ -303,8 +320,6 @@ func processErr(err error) {
 	}
 }
 
-var fset = token.NewFileSet()
-
 func writer(fname string) (w io.Writer, closer func()) {
 	if *outdir == "" {
 		return os.Stdout, func() { return }
diff --git a/cmd/gobind/main.go b/cmd/gobind/main.go
index 8ccb9951e..ab4970a04 100644
--- a/cmd/gobind/main.go
+++ b/cmd/gobind/main.go
@@ -9,6 +9,7 @@ import (
 	"flag"
 	"fmt"
 	"go/ast"
+	"go/token"
 	"go/types"
 	"io/ioutil"
 	"log"
@@ -145,18 +146,20 @@ func run() {
 
 	typePkgs := make([]*types.Package, len(allPkg))
 	astPkgs := make([][]*ast.File, len(allPkg))
+	fSets := make([]*token.FileSet, len(allPkg))
 	for i, pkg := range allPkg {
 		// Ignore pkg.Errors. pkg.Errors can exist when Cgo is used, but this should not affect the result.
 		// See the discussion at golang/go#36547.
 		typePkgs[i] = pkg.Types
 		astPkgs[i] = pkg.Syntax
+		fSets[i] = pkg.Fset
 	}
 	for _, l := range langs {
 		for i, pkg := range typePkgs {
-			genPkg(l, pkg, astPkgs[i], typePkgs, classes, otypes)
+			genPkg(l, fSets[i], pkg, astPkgs[i], typePkgs, classes, otypes)
 		}
 		// Generate the error package and support files
-		genPkg(l, nil, nil, typePkgs, classes, otypes)
+		genPkg(l, token.NewFileSet(), nil, nil, typePkgs, classes, otypes)
 	}
 }
 
diff --git a/cmd/gomobile/bind_androidapp.go b/cmd/gomobile/bind_androidapp.go
index 8fe91793d..f7c809744 100644
--- a/cmd/gomobile/bind_androidapp.go
+++ b/cmd/gomobile/bind_androidapp.go
@@ -29,6 +29,8 @@ func goAndroidBind(gobind string, pkgs []*packages.Package, androidArchs []strin
 		"-lang=go,java",
 		"-outdir="+tmpdir,
 	)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
 	cmd.Env = append(cmd.Env, "GOOS=android")
 	cmd.Env = append(cmd.Env, "CGO_ENABLED=1")
 	if len(buildTags) > 0 {
diff --git a/cmd/gomobile/bind_iosapp.go b/cmd/gomobile/bind_iosapp.go
index 91d0de3ae..90f537597 100644
--- a/cmd/gomobile/bind_iosapp.go
+++ b/cmd/gomobile/bind_iosapp.go
@@ -7,6 +7,7 @@ package main
 import (
 	"fmt"
 	"io"
+	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
@@ -22,6 +23,8 @@ func goIOSBind(gobind string, pkgs []*packages.Package, archs []string) error {
 		"-lang=go,objc",
 		"-outdir="+tmpdir,
 	)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
 	cmd.Env = append(cmd.Env, "GOOS=darwin")
 	cmd.Env = append(cmd.Env, "CGO_ENABLED=1")
 	tags := append(buildTags, "ios")