From f5c2cf0fa320d446ef2c289df83ef528feba30e1 Mon Sep 17 00:00:00 2001
From: Alexey Andreev <konsoletyper@gmail.com>
Date: Thu, 16 May 2019 18:50:03 +0300
Subject: [PATCH] C: fix generation of virtual tables inheriting interface
 default methods

---
 .../backend/c/generate/CallSiteGenerator.java |  6 ++++++
 .../backend/c/generate/ClassGenerator.java    |  1 -
 .../model/classes/VirtualTableProvider.java   | 19 +++++++++++++------
 3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/core/src/main/java/org/teavm/backend/c/generate/CallSiteGenerator.java b/core/src/main/java/org/teavm/backend/c/generate/CallSiteGenerator.java
index 81852480b..240d10389 100644
--- a/core/src/main/java/org/teavm/backend/c/generate/CallSiteGenerator.java
+++ b/core/src/main/java/org/teavm/backend/c/generate/CallSiteGenerator.java
@@ -114,6 +114,9 @@ public class CallSiteGenerator {
     }
 
     private void generateLocations() {
+        if (locations.isEmpty()) {
+            return;
+        }
         includes.includeClass(CALL_SITE_LOCATION);
         writer.print("static ").print(callSiteLocationName).print(" callSiteLocations_" + callSitesName
                 + "[" + locations.size() + "] = {").indent();
@@ -147,6 +150,9 @@ public class CallSiteGenerator {
     }
 
     private void generateHandlers() {
+        if (exceptionHandlers.isEmpty()) {
+            return;
+        }
         includes.includeClass(EXCEPTION_HANDLER);
         writer.print("static ").print(exceptionHandlerName).print(" exceptionHandlers_" + callSitesName + "["
                 + exceptionHandlers.size() + "] = {").indent();
diff --git a/core/src/main/java/org/teavm/backend/c/generate/ClassGenerator.java b/core/src/main/java/org/teavm/backend/c/generate/ClassGenerator.java
index b364133e4..0ca44822b 100644
--- a/core/src/main/java/org/teavm/backend/c/generate/ClassGenerator.java
+++ b/core/src/main/java/org/teavm/backend/c/generate/ClassGenerator.java
@@ -613,7 +613,6 @@ public class ClassGenerator {
         codeWriter.println(".superclass = " + parent + ",");
         codeWriter.println(".superinterfaceCount = " + superinterfaceCount + ",");
         codeWriter.println(".superinterfaces = " + superinterfaces + ",");
-        codeWriter.println(".enumValues = NULL,");
         codeWriter.println(".layout = " + layout + ",");
         codeWriter.println(".enumValues = " + enumConstants + ",");
         codeWriter.println(".init = " + initFunction);
diff --git a/core/src/main/java/org/teavm/model/classes/VirtualTableProvider.java b/core/src/main/java/org/teavm/model/classes/VirtualTableProvider.java
index e4f853133..915bb6a52 100644
--- a/core/src/main/java/org/teavm/model/classes/VirtualTableProvider.java
+++ b/core/src/main/java/org/teavm/model/classes/VirtualTableProvider.java
@@ -69,12 +69,11 @@ public class VirtualTableProvider {
         }
         if (cls.getParent() != null) {
             fillClass(cls.getParent(), methodCalledVirtually);
-            VirtualTable parentTable = virtualTables.get(cls.getParent());
-            for (VirtualTableEntry parentEntry : parentTable.entries.values()) {
-                VirtualTableEntry entry = new VirtualTableEntry(table, parentEntry.getMethod(),
-                        parentEntry.getImplementor(), parentEntry.getIndex());
-                table.entries.put(entry.getMethod(), entry);
-            }
+            copyEntriesFromSupertype(table, virtualTables.get(cls.getParent()));
+        }
+        for (String itf : cls.getInterfaces()) {
+            fillClass(itf, methodCalledVirtually);
+            copyEntriesFromSupertype(table, virtualTables.get(itf));
         }
 
         Set<MethodDescriptor> newDescriptors = virtualMethodMap.get(className);
@@ -106,6 +105,14 @@ public class VirtualTableProvider {
         }
     }
 
+    private void copyEntriesFromSupertype(VirtualTable table, VirtualTable supertypeTable) {
+        for (VirtualTableEntry parentEntry : supertypeTable.entries.values()) {
+            VirtualTableEntry entry = new VirtualTableEntry(table, parentEntry.getMethod(),
+                    parentEntry.getImplementor(), parentEntry.getIndex());
+            table.entries.put(entry.getMethod(), entry);
+        }
+    }
+
     public VirtualTableEntry lookup(MethodReference method) {
         VirtualTable vtable = virtualTables.get(interfaceMapping.mapClass(method.getClassName()));
         if (vtable == null) {