When opening the Java Sound Synthesizer implicitly, a following crash occures. Implicit open is done in the attached version of MidiSystem.java in the method getReceiver(). This version of MidiSystem was modified to implement a more backward-compatible semantics of getReceiver (allowing to get Receivers from Synthesizers, not only from MIDI port devices). See bug #4934509: Document explicitely MidiSystem.getReceiver's behavior. DefaultDevices.java can be used to reproduce the crash.
crash dump:
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#
# An unexpected error has been detected by HotSpot Virtual Machine:
#
# SIGSEGV (0xb) at pc=0x4cfd5aee, pid=25440, tid=1024
#
# Java VM: Java HotSpot(TM) Client VM (1.5.0-beta-b21 mixed mode)
# Problematic frame:
# C [libjsound.so+0x21aee] PV_ResetControlers+0x2a
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# An error report file with more information is saved as hs_err_pid25440.log
#
# If you would like to submit a bug report, please visit:
# http://java.sun.com/cgi-bin/bugreport.cgi
#
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