We don't support -verbose:jni, but we could. We could also support -verbose:gc (to some extent), and, with the BC ABI, could even add a tracing option to trace all calls.
-- Summary: gij should support -verbose:jni Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: enhancement Priority: P2 Component: libgcj AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: tromey at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org,java-prs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20087