bug in compiling not

[Felix S Klock II <pnkfelix at MIT dot EDU>]

Kawa list-

There is a bug in Kawa's compilation of the 'not' procedure; it only
shows up during compilation of a scheme program, not during
interpretation of it.

I've included a workaround that disables the offending code segment; I
don't understand enough about the design of the system to provide a
better fix.

-Felix


-- test file: "kawa-is-broken.scm" --

(define (break) 
  (let ((f #f))
    (not f)))


-- command line to compile file -- 

% java -jar kawa-1.6.95.jar -C kawa-is-broken.scm


-- stack trace due to exception throw by compiler --

java.lang.Error: non-matching or bad types in binary operation
        at java.lang.Throwable.<init>(Throwable.java:96)
        at java.lang.Error.<init>(Error.java:52)
        at gnu.bytecode.CodeAttr.emitBinop(CodeAttr.java:772)
        at gnu.bytecode.CodeAttr.emitAdd(CodeAttr.java:801)
        at gnu.bytecode.CodeAttr.emitNot(CodeAttr.java:821)
        at kawa.standard.not.compile(not.java:50)
        at gnu.expr.ApplyExp.compile(ApplyExp.java:158)
        at gnu.expr.ApplyExp.compile(ApplyExp.java:115)
        at gnu.expr.Expression.compileNotePosition(Expression.java:60)
        at gnu.expr.Expression.compileWithPosition(Expression.java:47)
        at gnu.expr.LetExp.compile(LetExp.java:73)
        at gnu.expr.Expression.compileNotePosition(Expression.java:60)
        at gnu.expr.Expression.compileWithPosition(Expression.java:47)
        at gnu.expr.LambdaExp.compileBody(LambdaExp.java:1411)
        at gnu.expr.LambdaExp.compileAsMethod(LambdaExp.java:1383)
        at gnu.expr.LambdaExp.compileSetField(LambdaExp.java:577)
        at gnu.expr.SetExp.compile(SetExp.java:142)
        at gnu.expr.Expression.compileNotePosition(Expression.java:60)
        at gnu.expr.Expression.compileWithPosition(Expression.java:47)
        at gnu.expr.LambdaExp.compileBody(LambdaExp.java:1411)
        at gnu.expr.Compilation.addClass(Compilation.java:1154)
        at gnu.expr.Compilation.<init>(Compilation.java:633)
        at gnu.expr.ModuleExp.compileToFiles(ModuleExp.java:272)
        at kawa.lang.CompileFile.compile_to_files(CompileFile.java:104)
        at kawa.repl.main(repl.java:191)


-- cvs diff -u against workaround (hack, not desired solution) --

Index: kawa/standard/not.java
===================================================================
RCS file: /cvs/kawa/kawa/kawa/standard/not.java,v
retrieving revision 1.12
diff -u -r1.12 not.java
--- not.java    2000/10/12 18:43:56     1.12
+++ not.java    2001/08/13 07:52:13
@@ -44,7 +44,7 @@
       }
     CodeAttr code = comp.getCode();
     Type type = target.getType();
-    if (target instanceof StackTarget && type.getSignature().charAt(0) == 'Z')
+    if (false && target instanceof StackTarget && type.getSignature().charAt(0) == 'Z')
       {
        arg.compile(comp, target);
        code.emitNot(target.getType());