Hello,

Local variables introduced in 1.0.46 broke debugger at least on Sun/Windows JVMs. JVM fails only when we're retrieving localVariables JVM responds with following error message:

"com.sun.jdi.InternalException: Got error code in reply: 35 occurred retrieving this from stack frame."

Where 35 is: Invalid_slot error.

Everything else works fine...

We have inspected byte-code generated by Fan and found out that Local variable table has no entry for this. However Java Compiler adds this entry in local variable table on the similar code.

Here is the patch which adds this entry to the Local variable table which fixes a problem:

diff -r 276896f3d6d7 src/sys/java/fanx/emit/FCodeEmit.java
--- a/src/sys/java/fanx/emit/FCodeEmit.java	Thu Sep 24 08:46:10 2009 -0400
+++ b/src/sys/java/fanx/emit/FCodeEmit.java	Fri Sep 25 19:22:30 2009 +0700
@@ -262,7 +262,15 @@
     AttrEmit attr = code.emitAttr("LocalVariableTable");
     Box info = attr.info;
     FMethodVar[] vars = fmethod.vars;
-    int offset = fmethod.isStatic() ? 0 : 1;
+
+    if(!fmethod.isStatic()){
+      FMethodVar thisVar = new FMethodVar();
+      thisVar.name = "this";
+      thisVar.type = parent.type.self;
+      vars = new FMethodVar[fmethod.vars.length + 1];
+      System.arraycopy(fmethod.vars, 0, vars, 1, fmethod.vars.length);
+      vars[0] = thisVar;
+    }
 
     // Fan variables never reuse stack registers, so
     // we can declare their scope across entire method
@@ -275,7 +283,7 @@
       info.u2(code.info.len-2-2-4); // max stack, max locals, code len
       info.u2(code.emit.utf(var.name));
       info.u2(code.emit.utf(pod.typeRef(var.type).jsig()));
-      info.u2(i+offset);
+      info.u2(i);
     }
   }

-- Best regards, Ivan Lobachev

Thanks Ivan - I'll let Brian take a look when he gets back from CA Sun.

I pushed a fix to hg: changeset

I reworked your suggested patch to avoid copying the whole array. Thanks much for submitting a fix!

Let me know how that works for you.

Thanks a lot Brian! It works fine now.