java compiler generates inaccurate LineNumberTable attribute

1-14


======================================================================


Name: dkC59003 Date: 01/13/2000



See below the java source code with line numbers and the corresponding
class files compiled by the JDK 1.3.OR and JDK 1.2.2 compilers.

This is the LineNumberTable for the <clinit> method compiled
by the JDK 1.3.OR compiler:

              [] { // LineNumberTable
                0 23;
                5 24;
                16 27;
                25 21;
The last line is questionable: the code index value 25
corresponds to the return instruction (byte code B1)
but the line number indicates the first line of this method.
This LineNumberTable item differs from the one for
the test_method() method:

              [] { // LineNumberTable
                0 11;
                2 12;
                10 13;
where the line number (13) looks right.



This is the LineNumberTable for the <clinit> method compiled
by the JDK 1.2.2 compiler:

              [] { // LineNumberTable
                0 22;
                0 23;
                5 24;
                13 22;
                16 26;
                17 27;
                25 1;
The LineNumberTable items in the fourth and in the last lines
look invalid.

The last line in the LineNumberTable for the test_method() method
compiled by the JDK 1.2.2 compiler:
              [] { // LineNumberTable
                0 11;
                2 12;
                10 10;
looks invalid too.


------------------------- java source --------------------------
 1 public class b4301835 {
 2
 3 public static int run(String argv[], java.io.PrintStream out) {
 4 if ( checkLineNumberTable() == -1 ) {
 5 return 2/*STATUS_FAILED*/;
 6 }
 7 return 0/*STATUS_PASSED*/;
 8 }
 9
10 static void test_method() {
11 int localInt = 3;
12 System.out.println("----> b4301835: test_method is running");
13 }
14
15 public static void main(String argv[]) {
16 System.exit(run(argv, System.out) + 95/*STATUS_TEMP*/);
17 }
18
19 native static int checkLineNumberTable();
20
21 static {
22 try {
23 System.loadLibrary("b4301835");
24 System.out.println("----> loadLibrary(\"b4301835\") - COMPLETED");
25 }
26 catch (UnsatisfiedLinkError ule) {
27 System.out.println("----> Could not load b4301835 library");
28 }
29 }
30
31 } // end of b4301835 class
------------------------- java source end --------------------------

-------------- class file compiled by JDK 1.3.0R compiler ----------
class b4301835 {
  0xCAFEBABE;
  3; // minor version
  45; // version
  [] { // Constant Pool
    ; // first element is empty
    Method #14 #29; // #1
    Method #13 #30; // #2
    Field #31 #32; // #3
    String #33; // #4
    Method #34 #35; // #5
    Method #13 #36; // #6
    Method #31 #37; // #7
    String #38; // #8
    Method #31 #39; // #9
    String #40; // #10
    class #41; // #11
    String #42; // #12
    class #38; // #13
    class #43; // #14
    Utf8 "<init>"; // #15
    Utf8 "()V"; // #16
    Utf8 "Code"; // #17
    Utf8 "LineNumberTable"; // #18
    Utf8 "run"; // #19
    Utf8 "([Ljava/lang/String;Ljava/io/PrintStream;)I"; // #20
    Utf8 "test_method"; // #21
    Utf8 "main"; // #22
    Utf8 "([Ljava/lang/String;)V"; // #23
    Utf8 "checkLineNumberTable"; // #24
    Utf8 "()I"; // #25
    Utf8 "<clinit>"; // #26
    Utf8 "SourceFile"; // #27
    Utf8 "b4301835.java"; // #28
    NameAndType #15 #16; // #29
    NameAndType #24 #25; // #30
    class #44; // #31
    NameAndType #45 #46; // #32
    Utf8 "----> b4301835: test_method is running"; // #33
    class #47; // #34
    NameAndType #48 #49; // #35
    NameAndType #19 #20; // #36
    NameAndType #50 #51; // #37
    Utf8 "b4301835"; // #38
    NameAndType #52 #49; // #39
    Utf8 "----> loadLibrary(\"b4301835\") - COMPLETED"; // #40
    Utf8 "java/lang/UnsatisfiedLinkError"; // #41
    Utf8 "----> Could not load b4301835 library"; // #42
    Utf8 "java/lang/Object"; // #43
    Utf8 "java/lang/System"; // #44
    Utf8 "out"; // #45
    Utf8 "Ljava/io/PrintStream;"; // #46
    Utf8 "java/io/PrintStream"; // #47
    Utf8 "println"; // #48
    Utf8 "(Ljava/lang/String;)V"; // #49
    Utf8 "exit"; // #50
    Utf8 "(I)V"; // #51
    Utf8 "loadLibrary"; // #52
  } // Constant Pool

  0x0021; // access
  #13;// this_cpx
  #14;// super_cpx

  [] { // Interfaces
  } // Interfaces

  [] { // fields
  } // fields

  [] { // methods
    { // Member
      0x0001; // access
      #15; // name_cpx
      #16; // sig_cpx
      [] { // Attributes
        Attr(#17) { // Code
          1; // max_stack
          1; // max_locals
          Bytes[] {
            0x2AB70001B1;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#18) { // LineNumberTable
              [] { // LineNumberTable
                0 1;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0009; // access
      #19; // name_cpx
      #20; // sig_cpx
      [] { // Attributes
        Attr(#17) { // Code
          2; // max_stack
          2; // max_locals
          Bytes[] {
            0xB8000202A0000505;
            0xAC03AC;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#18) { // LineNumberTable
              [] { // LineNumberTable
                0 4;
                7 5;
                9 7;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0008; // access
      #21; // name_cpx
      #16; // sig_cpx
      [] { // Attributes
        Attr(#17) { // Code
          2; // max_stack
          1; // max_locals
          Bytes[] {
            0x063BB200031204B6;
            0x0005B1;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#18) { // LineNumberTable
              [] { // LineNumberTable
                0 11;
                2 12;
                10 13;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0009; // access
      #22; // name_cpx
      #23; // sig_cpx
      [] { // Attributes
        Attr(#17) { // Code
          2; // max_stack
          1; // max_locals
          Bytes[] {
            0x2AB20003B8000610;
            0x5F60B80007B1;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#18) { // LineNumberTable
              [] { // LineNumberTable
                0 16;
                13 17;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0108; // access
      #24; // name_cpx
      #25; // sig_cpx
      [] { // Attributes
      } // Attributes
    } // Member
    ;
    { // Member
      0x0008; // access
      #26; // name_cpx
      #16; // sig_cpx
      [] { // Attributes
        Attr(#17) { // Code
          2; // max_stack
          1; // max_locals
          Bytes[] {
            0x1208B80009B20003;
            0x120AB60005A7000C;
            0x4BB20003120CB600;
            0x05B1;
          };
          [] { // Traps
            0 13 16 11;
          } // end Traps
          [] { // Attributes
            Attr(#18) { // LineNumberTable
              [] { // LineNumberTable
                0 23;
                5 24;
                16 27;
                25 21;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
  } // methods

  [] { // Attributes
    Attr(#27) { // SourceFile
      #28;
    } // end SourceFile
  } // Attributes
} // end class b4301835

--------------------------------------------------------------------

-------------- class file compiled by JDK 1.2.2 compiler ----------
class b4301835 {
  0xCAFEBABE;
  3; // minor version
  45; // version
  [] { // Constant Pool
    ; // first element is empty
    String #30; // #1
    String #31; // #2
    String #32; // #3
    String #39; // #4
    class #39; // #5
    class #43; // #6
    class #44; // #7
    class #45; // #8
    class #46; // #9
    Method #7 #17; // #10
    Method #5 #18; // #11
    Method #8 #19; // #12
    Method #8 #20; // #13
    Field #8 #21; // #14
    Method #6 #22; // #15
    Method #5 #23; // #16
    NameAndType #34 #25; // #17
    NameAndType #41 #24; // #18
    NameAndType #42 #26; // #19
    NameAndType #47 #27; // #20
    NameAndType #49 #37; // #21
    NameAndType #50 #27; // #22
    NameAndType #51 #29; // #23
    Utf8 "()I"; // #24
    Utf8 "()V"; // #25
    Utf8 "(I)V"; // #26
    Utf8 "(Ljava/lang/String;)V"; // #27
    Utf8 "([Ljava/lang/String;)V"; // #28
    Utf8 "([Ljava/lang/String;Ljava/io/PrintStream;)I"; // #29
    Utf8 "----> Could not load b4301835 library"; // #30
    Utf8 "----> b4301835: test_method is running"; // #31
    Utf8 "----> loadLibrary(\"b4301835\") - COMPLETED"; // #32
    Utf8 "<clinit>"; // #33
    Utf8 "<init>"; // #34
    Utf8 "Code"; // #35
    Utf8 "LineNumberTable"; // #36
    Utf8 "Ljava/io/PrintStream;"; // #37
    Utf8 "SourceFile"; // #38
    Utf8 "b4301835"; // #39
    Utf8 "b4301835.java"; // #40
    Utf8 "checkLineNumberTable"; // #41
    Utf8 "exit"; // #42
    Utf8 "java/io/PrintStream"; // #43
    Utf8 "java/lang/Object"; // #44
    Utf8 "java/lang/System"; // #45
    Utf8 "java/lang/UnsatisfiedLinkError"; // #46
    Utf8 "loadLibrary"; // #47
    Utf8 "main"; // #48
    Utf8 "out"; // #49
    Utf8 "println"; // #50
    Utf8 "run"; // #51
    Utf8 "test_method"; // #52
  } // Constant Pool

  0x0021; // access
  #5;// this_cpx
  #7;// super_cpx

  [] { // Interfaces
  } // Interfaces

  [] { // fields
  } // fields

  [] { // methods
    { // Member
      0x0008; // access
      #33; // name_cpx
      #25; // sig_cpx
      [] { // Attributes
        Attr(#35) { // Code
          2; // max_stack
          0; // max_locals
          Bytes[] {
            0x1204B8000DB2000E;
            0x1203B6000FA7000C;
            0x57B2000E1201B600;
            0x0FB1;
          };
          [] { // Traps
            0 13 16 9;
          } // end Traps
          [] { // Attributes
            Attr(#36) { // LineNumberTable
              [] { // LineNumberTable
                0 22;
                0 23;
                5 24;
                13 22;
                16 26;
                17 27;
                25 1;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0001; // access
      #34; // name_cpx
      #25; // sig_cpx
      [] { // Attributes
        Attr(#35) { // Code
          1; // max_stack
          1; // max_locals
          Bytes[] {
            0x2AB7000AB1;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#36) { // LineNumberTable
              [] { // LineNumberTable
                0 1;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0108; // access
      #41; // name_cpx
      #24; // sig_cpx
      [] { // Attributes
      } // Attributes
    } // Member
    ;
    { // Member
      0x0009; // access
      #48; // name_cpx
      #28; // sig_cpx
      [] { // Attributes
        Attr(#35) { // Code
          2; // max_stack
          1; // max_locals
          Bytes[] {
            0x2AB2000EB8001010;
            0x5F60B8000CB1;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#36) { // LineNumberTable
              [] { // LineNumberTable
                0 16;
                13 15;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0009; // access
      #51; // name_cpx
      #29; // sig_cpx
      [] { // Attributes
        Attr(#35) { // Code
          2; // max_stack
          2; // max_locals
          Bytes[] {
            0xB8000B02A0000505;
            0xAC03AC;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#36) { // LineNumberTable
              [] { // LineNumberTable
                0 4;
                7 5;
                9 7;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
    ;
    { // Member
      0x0008; // access
      #52; // name_cpx
      #25; // sig_cpx
      [] { // Attributes
        Attr(#35) { // Code
          2; // max_stack
          1; // max_locals
          Bytes[] {
            0x063BB2000E1202B6;
            0x000FB1;
          };
          [] { // Traps
          } // end Traps
          [] { // Attributes
            Attr(#36) { // LineNumberTable
              [] { // LineNumberTable
                0 11;
                2 12;
                10 10;
              }
            } // end LineNumberTable
          } // Attributes
        } // end Code
      } // Attributes
    } // Member
  } // methods

  [] { // Attributes
    Attr(#38) { // SourceFile
      #40;
    } // end SourceFile
  } // Attributes
} // end class b4301835
--------------------------------------------------------------------


======================================================================

Name: dkC59003 Date: 01/14/2000



Addition:

The LineNumberTable items for the <clinit> method compiled
by the JDK 1.2.2 compiler:

                16 26;
                17 27;
look more preferable than the item for the <clinit> method
compiled by the JDK 1.3.OR compiler:

                16 27;

The code index value 16 corresponds to the beginning of the catch block
and the corresponding source line is

26 catch (UnsatisfiedLinkError ule) {

The code index value 17 corresponds to the beginning of the println(...)
method call and the corresponding source line is

27 System.out.println("----> Could not load b4301835 library");


###@###.### 2000-0