properly serialize/parse Nothing type

compiler/backend/src/org/jetbrains/jet/codegen/BothSignatureWriter.java

@@ -167,6 +167,22 @@ public class BothSignatureWriter {
         jetSignatureWriter.visitBaseType(c, nullable);
         writeAsmType0(Type.getType(String.valueOf(c)));
     }
+
+    public void writeNothing(boolean nullable) {
+        if (nullable) {
+            signatureVisitor().visitClassType("java/lang/Object");
+            signatureVisitor().visitEnd();
+        } else {
+            signatureVisitor().visitBaseType('V');
+        }
+        jetSignatureWriter.visitClassType("jet/Nothing", nullable, false);
+        jetSignatureWriter.visitEnd();
+        if (nullable) {
+            writeAsmType0(JetTypeMapper.TYPE_OBJECT);
+        } else {
+            writeAsmType0(Type.VOID_TYPE);
+        }
+    }
     
     private String makeArrayPrefix() {
         StringBuilder sb = new StringBuilder();

compiler/backend/src/org/jetbrains/jet/codegen/JetTypeMapper.java

@@ -121,15 +121,21 @@ public class JetTypeMapper {
     }
 
     @NotNull private Type mapReturnType(final JetType jetType, @Nullable BothSignatureWriter signatureVisitor) {
-        if (jetType.equals(JetStandardClasses.getUnitType()) || jetType.equals(JetStandardClasses.getNothingType())) {
+        if (jetType.equals(JetStandardClasses.getUnitType())) {
             if (signatureVisitor != null) {
                 signatureVisitor.writeAsmType(Type.VOID_TYPE, false);
             }
             return Type.VOID_TYPE;
         }
+        else if (jetType.equals(JetStandardClasses.getNothingType())) {
+            if (signatureVisitor != null) {
+                signatureVisitor.writeNothing(false);
+            }
+            return Type.VOID_TYPE;
+        }
         if (jetType.equals(JetStandardClasses.getNullableNothingType())) {
             if (signatureVisitor != null) {
-                visitAsmType(signatureVisitor, TYPE_OBJECT, false);
+                signatureVisitor.writeNothing(true);
             }
             return TYPE_OBJECT;
         }

compiler/testData/readKotlinBinaryClass/type/Nothing.kt

@@ -0,0 +1,3 @@
+package test
+
+fun nothing(): Nothing = throw Exception()

compiler/testData/readKotlinBinaryClass/type/NothingQ.kt

@@ -0,0 +1,3 @@
+package test
+
+fun nothingq(): Nothing? = null

compiler/testData/writeSignature/Nothing.kt

@@ -0,0 +1,6 @@
+fun nothing(): Nothing = throw Exception()
+
+// method: namespace::nothing
+// jvm signature:     ()V
+// generic signature: null
+// kotlin signature:  ()Ljet/Nothing;

compiler/testData/writeSignature/NothingQ.kt

@@ -0,0 +1,6 @@
+fun nothingq(): Nothing? = null
+
+// method: namespace::nothingq
+// jvm signature:     ()Ljava/lang/Object;
+// generic signature: null
+// kotlin signature:  ()?Ljet/Nothing;