Name: ssT124754 Date: 01/24/2001


The new javac from 1.3 compiles illegal code.
E.g.:

public class IllegalExpressionTest
{
    public static void main(String[] args)
    {
        (System.out.println());
        // I don't see a valid production for this statement in the Java grammar
    }
}


javac from 1.3 compiles this code as if the parentheses were not present:
% javac IllegalExpressionTest.java
% javap -c IllegalExpressionTest
Compiled from IllegalExpressionTest.java
public class IllegalExpressionTest extends java.lang.Object {
    public IllegalExpressionTest();
    public static void main(java.lang.String[]);
}

Method IllegalExpressionTest()
   0 aload_0
   1 invokespecial #1 <Method java.lang.Object()>
   4 return

Method void main(java.lang.String[])
   0 getstatic #2 <Field java.io.PrintStream out>
   3 invokevirtual #3 <Method void println()>
   6 return


oldjavac, gcj, jikes and javadoc correctly issue an error message:
% oldjavac IllegalExpressionTest.java
IllegalExpressionTest.java:5: Invalid expression statement.
        (System.out.println());
        ^
1 error
% gcj IllegalExpressionTest.java
IllegalExpressionTest.java:5: Invalid expression statement.
        (System.out.println());
                              ^
1 error
% jikes IllegalExpressionTest.java

Found 1 syntax error in "IllegalExpressionTest.java":

     5. (System.out.println());
                                     ^
*** Syntax Error: ++ expected after this token
% javadoc IllegalExpressionTest.java
Loading source file IllegalExpressionTest.java...
IllegalExpressionTest.java:5: Invalid expression statement.
        (System.out.println());
        ^
1 error
(Review ID: 111407)
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