Updates: Summary: Comment #2 on issue 120 by nicolas.... at gmail.com: http://code.google.com/p/cog/issues/detail?id=120 No crash when compiling a SimpleStackBasedCogit with gcc 4.6.3 The crash only occurs with a StackToRegisterMappingCogit... Prsumably, gcc and cog jit disagree on which registers are/should be preserved...