Running the dacapo lusearch benchmark on dual- and quad-core machines frequently leads to unwarranted SIGSEGVs or heap corruptions detected by glibc. On average, 1 out of 20 runs fails with SIGABRT because of this. Spurious NullPointerExceptions or ClassCastExceptions happen also from time to time. When trying to trigger those failures, it seems to help to load the machine a bit. The most frequent cause of failure is a heap corruption in dumpmemory_release followed by a crash inside the compiler while another thread does GC. SIGSEGV inside builtin_arraycopy is also one of the more frequent occurences. The version tested was 056edaebc79b with classpath 0.96.1 on four different Linux machines, all x86_64. Two quad-cores, two dual-cores, two of them running CentOS 5, one Fedora 5 and one Fedora 8. All four behave essentially the same.