diff --git a/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingContext.java b/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingContext.java
index 0e401c21c..cd6a0bd6b 100644
--- a/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingContext.java
+++ b/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingContext.java
@@ -216,7 +216,7 @@ public class RenderingContext {
     }
 
     public String mainLoopName() {
-        return minifying ? "$m" : "$main";
+        return minifying ? "_" : "main";
     }
 
     public String tempVarName() {
diff --git a/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingUtil.java b/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingUtil.java
index 226925e95..5e6fdd700 100644
--- a/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingUtil.java
+++ b/core/src/main/java/org/teavm/backend/javascript/rendering/RenderingUtil.java
@@ -76,6 +76,7 @@ public final class RenderingUtil {
     public static String indexToId(int index) {
         StringBuilder sb = new StringBuilder();
         sb.append(variableNames.charAt(index % variableNames.length()));
+        index /= variableNames.length();
         while (index > 0) {
             sb.append(variablePartNames.charAt(index % variablePartNames.length()));
             index /= variablePartNames.length();
diff --git a/core/src/main/java/org/teavm/backend/javascript/rendering/StatementRenderer.java b/core/src/main/java/org/teavm/backend/javascript/rendering/StatementRenderer.java
index 8b556b302..0c6d7c5bb 100644
--- a/core/src/main/java/org/teavm/backend/javascript/rendering/StatementRenderer.java
+++ b/core/src/main/java/org/teavm/backend/javascript/rendering/StatementRenderer.java
@@ -307,7 +307,7 @@ public class StatementRenderer implements ExprVisitor, StatementVisitor {
         String name = blockIdMap.get(id);
         if (name == null) {
             int index = blockIdMap.size();
-            name = "$b" + RenderingUtil.indexToId(index);
+            name = RenderingUtil.indexToId(index);
             blockIdMap.put(id, name);
         }
         return name;