I found that the Mantis javac throws an error trying to compile the java/src/ tree of NetBeans sources. These sources are used by both the NetBeans and Sun ONE Studio IDEs. The error seems reproducible in both the NetBeans CVS trunk and on the release35 branch used also by S1S "Nevada" ~ 5.0. Only checked on Linux.

I managed to extract all relevant files into one bundle. Unpack it (tar xvfz) and do

cd javacbug
./run.sh

with the JDK's bin/ dir in your path. I get an error under JDK 1.4.2 b11 and b18, but not in 1.4.1_01:

javacbug$ PATH=/space/jdk1.4.1_01/bin:$PATH ./run.sh
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)
Note: Some input files use or override a deprecated API.
Note: Recompile with -deprecation for details.

javacbug$ PATH=/space/jdk1.4.2-beta-b18/bin:$PATH ./run.sh
java version "1.4.2-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2-beta-b18)
Java HotSpot(TM) Client VM (build 1.4.2-beta-b18, mixed mode)
An exception has occurred in the compiler (1.4.2-beta). Please file a bug at the Java Developer Connection (http://java.sun.com/cgi-bin/bugreport.cgi) after checking the Bug Parade for duplicates. Include your program and the following diagnostic in your report. Thank you.
java.lang.NullPointerException
at com.sun.tools.javac.v8.comp.Flow.checkInit(Flow.java:380)
at com.sun.tools.javac.v8.comp.Flow.visitIdent(Flow.java:1131)
at com.sun.tools.javac.v8.tree.Tree$Ident.accept(Tree.java:1111)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.tree.TreeScanner.visitSelect(TreeScanner.java:242)
at com.sun.tools.javac.v8.tree.Tree$Select.accept(Tree.java:1091)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanExpr(Flow.java:501)
at com.sun.tools.javac.v8.comp.Flow.visitBinary(Flow.java:1123)
at com.sun.tools.javac.v8.tree.Tree$Binary.accept(Tree.java:1014)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:42)
at com.sun.tools.javac.v8.tree.TreeScanner.visitNewArray(TreeScanner.java:200)
at com.sun.tools.javac.v8.tree.Tree$NewArray.accept(Tree.java:922)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanExpr(Flow.java:501)
at com.sun.tools.javac.v8.comp.Flow.visitVarDef(Flow.java:703)
at com.sun.tools.javac.v8.tree.Tree$VarDef.accept(Tree.java:511)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanStat(Flow.java:483)
at com.sun.tools.javac.v8.comp.Flow.scanStats(Flow.java:492)
at com.sun.tools.javac.v8.comp.Flow.visitBlock(Flow.java:711)
at com.sun.tools.javac.v8.tree.Tree$Block.accept(Tree.java:547)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanStat(Flow.java:483)
at com.sun.tools.javac.v8.comp.Flow.visitIf(Flow.java:996)
at com.sun.tools.javac.v8.tree.Tree$If.accept(Tree.java:756)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanStat(Flow.java:483)
at com.sun.tools.javac.v8.comp.Flow.scanStats(Flow.java:492)
at com.sun.tools.javac.v8.comp.Flow.visitBlock(Flow.java:711)
at com.sun.tools.javac.v8.tree.Tree$Block.accept(Tree.java:547)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanStat(Flow.java:483)
at com.sun.tools.javac.v8.comp.Flow.visitForLoop(Flow.java:793)
at com.sun.tools.javac.v8.tree.Tree$ForLoop.accept(Tree.java:605)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanStat(Flow.java:483)
at com.sun.tools.javac.v8.comp.Flow.scanStats(Flow.java:492)
at com.sun.tools.javac.v8.comp.Flow.visitBlock(Flow.java:711)
at com.sun.tools.javac.v8.tree.Tree$Block.accept(Tree.java:547)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.scanStat(Flow.java:483)
at com.sun.tools.javac.v8.comp.Flow.visitMethodDef(Flow.java:665)
at com.sun.tools.javac.v8.tree.Tree$MethodDef.accept(Tree.java:482)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.visitClassDef(Flow.java:615)
at com.sun.tools.javac.v8.tree.Tree$ClassDef.accept(Tree.java:443)
at com.sun.tools.javac.v8.tree.TreeScanner.scan(TreeScanner.java:33)
at com.sun.tools.javac.v8.comp.Flow.analyzeTree(Flow.java:1156)
at com.sun.tools.javac.v8.JavaCompiler.compile(JavaCompiler.java:361)
at com.sun.tools.javac.v8.Main.compile(Main.java:569)
at com.sun.tools.javac.Main.compile(Main.java:36)
at com.sun.tools.javac.Main.main(Main.java:27)

###@###.### 2003-03-14
###@###.### 2003-03-19