javac produces a compile error for valid java 7 codes: Cast vs Boolean Expression

[bitter_fox]

Hi,
I found a javac bug.

Javac reject valid java 7 codes:

public class Test
{
    static int a, b, c, d;

    public static void main(String[] args)
    {
        boolean cond = (a < b & c > d);

        /*
      JavacParser#analyzeParens
          LPAREN
          IDENT(a) : skip
          LT : depth = 1
          IDENT(b) : skip
          AMP : skip
          IDENT(c) : skip
          GT : depth = 0 -> type = true
          IDENT(d) : skip
          RPAREN : type == true -> return ParensResult.CAST
        */
    }
}

This is a simple parened boolean expression.
But javac(JavacParser#analyzeParens) analyzes it into CAST expression from
above.

Today's JavacParser#analyzeParens take no thought that intersection type
for type parameter isn't accepted.

You should change JavacParser#analyzeParens like following.

--- a/src/share/classes/com/sun/tools/javac/parser/JavacParser.java     Mon
Nov 11 23:16:35 2013 -0800
+++ b/src/share/classes/com/sun/tools/javac/parser/JavacParser.java     Tue
Nov 26 14:27:43 2013 +0900
@@ -1536,7 +1536,14 @@
             switch (tk) {
                 case COMMA:
                     type = true;
-                case EXTENDS: case SUPER: case DOT: case AMP:
+                    break;
+                case AMP:
+                    if (depth > 0) {
+                        // < ... & -> parens
+                        // (for type parameter, intersection type isn't
accepted)
+                        return ParensResult.PARENS;
+                    }
+                case EXTENDS: case SUPER: case DOT:
                     //skip
                     break;
                 case QUES:

Regards,
bitter_fox