OpenJDK: Getting closer to a full build

On friday I found the bug why Boehm always crashed with OpenJDK's wrappers. The problem is that the wrappers create a thread which then runs the VM. Boehm doesn't like that. But it can simply be removed:

Index: j2se/src/share/bin/java.c
===================================================================
--- j2se/src/share/bin/java.c   (revision 244)
+++ j2se/src/share/bin/java.c   (working copy)
@@ -367,7 +367,8 @@ main(int argc, char ** argv)
       args.classname = classname;
       args.ifn = ifn;
 
-      return ContinueInNewThread(JavaMain, threadStackSize,
(void*)&args, ret);
+/*       return ContinueInNewThread(JavaMain,
threadStackSize, (void*)&args, ret); */
+      return JavaMain((void*)&args);
     }
 }
 

With that patch we can use OpenJDK's wrappers with CACAO's libjvm:

$ java -version
LOG: [0x30021b70] JVM_GetStackAccessControlContext:
IMPLEMENT ME!
LOG: [0x30021b70] JVM_GetStackAccessControlContext:
IMPLEMENT ME!
LOG: [0x30021b70] JVM_FindSignal: name=HUP
LOG: [0x30021b70] JVM_RegisterSignal: sig=0, handler=0x2,
IMPLEMENT ME!
LOG: [0x30021b70] JVM_FindSignal: name=INT
LOG: [0x30021b70] JVM_RegisterSignal: sig=0, handler=0x2,
IMPLEMENT ME!
LOG: [0x30021b70] JVM_FindSignal: name=TERM
LOG: [0x30021b70] JVM_RegisterSignal: sig=0, handler=0x2,
IMPLEMENT ME!
LOG: [0x30021b70] JVM_GetStackAccessControlContext:
IMPLEMENT ME!
LOG: [0x30021b70] JVM_GetStackAccessControlContext:
IMPLEMENT ME!
openjdk version "1.7.0-internal-fastdebug"
OpenJDK Runtime Environment (build
1.7.0-internal-fastdebug-twisti_29_jul_2007_18_33-b00)
CACAO (build 0.98+svn, JIT mode)

WOOHOO! :-)

That means we can build OpenJDK with its own tools, by providing a CACAO-Sun build to OpenJDK with ALT_HOTSPOT_IMPORT_PATH. Then CACAO's libjvm gets imported and all tools like javac, javah or rmic are called from the currently builing OpenJDK.

With some small patches and the help of IcedTea I get a fully compiled and working j2re-image on my powerpc-linux box!!!

That is _really_ cool!

j2sdk-image is currently failing because of missing annotations support. But the student working on CACAO's annotations support already has a working implementation for OpenJDK and it will be (hopefully) commited tomorrow. That probably means a new blog soon...