Name: rmT116609 Date: 02/08/2004


FULL PRODUCT VERSION :
java version "1.5.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-beta-b32c)
Java HotSpot(TM) Client VM (build 1.5.0-beta-b32c, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux kernel 2.4.16-686 from Debian/Woody

A DESCRIPTION OF THE PROBLEM :
Compiler crashes processing source code which relies on auto-unboxing on RHS to perform +=, -=, *=, or /= against an unboxed value in LHS, like in:

double prim = 1.1;
Double boxed = 2.2;
prim += boxed;

The compiler does process other combinations correctly, such as:

prim += prim;
boxed += boxed;
boxed += prim;

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Attempt to compile a program with the described code segment using 'javac -source 1.5' and the 1.5.0 beta release.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Compiler should generate code which unboxes 'boxed' and (for +=) adds that value to 'prim'.
ACTUAL -
Compiler crash

ERROR MESSAGES/STACK TRACES THAT OCCUR :
An exception has occurred in the compiler (1.5.0-beta). Please file a bug at the Java Developer Connection (http://java.sun.com/cgi-bin/bugreport.cgi) after checking the Bug Parade for duplicates. Include your program and the following diagnostic in your report. Thank you.
java.lang.ArrayIndexOutOfBoundsException: -1
        at com.sun.tools.javac.jvm.Code$State.pop(Code.java:1509)
        at com.sun.tools.javac.jvm.Code.emitop0(Code.java:587)
        at com.sun.tools.javac.jvm.Items$Item.coerce(Items.java:236)
        at com.sun.tools.javac.jvm.Items$Item.coerce(Items.java:249)
        at com.sun.tools.javac.jvm.Gen.genExpr(Gen.java:806)
        at com.sun.tools.javac.jvm.Gen.completeBinop(Gen.java:1996)
        at com.sun.tools.javac.jvm.Gen.visitAssignop(Gen.java:1795)
        at com.sun.tools.javac.tree.Tree$Assignop.accept(Tree.java:899)
        at com.sun.tools.javac.jvm.Gen.genExpr(Gen.java:804)
        at com.sun.tools.javac.jvm.Gen.visitExec(Gen.java:1599)
        at com.sun.tools.javac.tree.Tree$Exec.accept(Tree.java:734)
        at com.sun.tools.javac.jvm.Gen.genDef(Gen.java:651)
        at com.sun.tools.javac.jvm.Gen.genStat(Gen.java:686)
        at com.sun.tools.javac.jvm.Gen.genStat(Gen.java:672)
        at com.sun.tools.javac.jvm.Gen.genStats(Gen.java:723)
        at com.sun.tools.javac.jvm.Gen.visitBlock(Gen.java:970)
        at com.sun.tools.javac.tree.Tree$Block.accept(Tree.java:540)
        at com.sun.tools.javac.jvm.Gen.genDef(Gen.java:651)
        at com.sun.tools.javac.jvm.Gen.genStat(Gen.java:686)
        at com.sun.tools.javac.jvm.Gen.genMethod(Gen.java:908)
        at com.sun.tools.javac.jvm.Gen.visitMethodDef(Gen.java:844)
        at com.sun.tools.javac.tree.Tree$MethodDef.accept(Tree.java:482)
        at com.sun.tools.javac.jvm.Gen.genDef(Gen.java:651)
        at com.sun.tools.javac.jvm.Gen.genClass(Gen.java:2177)
        at com.sun.tools.javac.main.JavaCompiler.genCode(JavaCompiler.java:325)
        at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:467)
        at com.sun.tools.javac.main.Main.compile(Main.java:593)
        at com.sun.tools.javac.main.Main.compile(Main.java:545)
        at com.sun.tools.javac.Main.compile(Main.java:44)
        at com.sun.tools.javac.Main.main(Main.java:35)


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
public class Wonk {
        public static void main(String[] args) {
                double prim = 1.1;
                Double boxed = 2.2;
                prim += boxed;
                                                                                
                System.out.printf("boxed=%4f prim=%4f\n", boxed, prim);
        }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Find a way to coerce 'boxed' to be unboxed. In the above code fragment, replace

prim += boxed;

with any of

prim += (double) boxed;
prim += boxed + 0.0;
prim = prim + boxed;
(Incident Review ID: 237782)
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