Weird problems compiling bytecode

[Edgar Villanueva <edgarvil at home dot com>]

I have been trying to compile the java antlr library in both source and
bytecode format.
I have been successful compiling the .java files but not the .class
files.

The antlr download is quite small and can be retrieved from here:
http://www.antlr.org/download.html

Environment:  Redhat 7 x86
Configured with: ../gcc/configure --prefix=/opt/gcc
--enable-threads=posix --enable-languages=c,c++,java
--enable-libstdcxx-v3 : (reconfigured)
gcc version 2.97 20010118 (experimental)

Here's what I get when I compile the class files and what I do to get
the errors:

[edgar@edgar4 antlr]$ javac -g *.java
[edgar@edgar4 antlr]$ gcj -c *.class

antlr/CppCodeGenerator.java: In class `antlr.CppCodeGenerator':
antlr/CppCodeGenerator.java: In method
`antlr.CppCodeGenerator(antlr.AlternativeBlock,boolean)':
antlr/CppCodeGenerator.java:1585: Tree check: expected integer_cst, have
instance_initializers_expr
antlr/CppCodeGenerator.java:1585: Internal compiler error in
verify_jvm_instructions, at java/verify.c:966
Please submit a full bug report.
 See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
antlr/JavaCodeGenerator.java: In class `antlr.JavaCodeGenerator':
antlr/JavaCodeGenerator.java: In method
`antlr.JavaCodeGenerator(antlr.Alternative,int)':
antlr/JavaCodeGenerator.java:2769: Tree check: expected integer_cst,
have instance_initializers_expr
antlr/JavaCodeGenerator.java:2769: Internal compiler error in
verify_jvm_instructions, at java/verify.c:966
Please submit a full bug report.
 See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
antlr/SatherCodeGenerator.java: In class `antlr.SatherCodeGenerator':
antlr/SatherCodeGenerator.java: In method
`antlr.SatherCodeGenerator(antlr.Alternative,int)':
antlr/SatherCodeGenerator.java:2906: Tree check: expected integer_cst,
have instance_initializers_expr
antlr/SatherCodeGenerator.java:2906: Internal compiler error in
verify_jvm_instructions, at java/verify.c:966
Please submit a full bug report.
 See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
antlr/Tool.java: In class `antlr.Tool':
antlr/Tool.java: In method `antlr.Tool(java.lang.String,char)':
antlr/Tool.java:389: warning: Unreachable bytecode from 26 to before 29.