87:  Why does Emacs 18.55 say `Fatal error (6).Abort' under SunOS 4.1?
  
  I had hoped this question would go away after Emacs 18.57 was released,
  but people continue to compile 18.55.  Easiest solution: upgrade.
  
  This is a result of the SunOS localtime/tzsetwall malloc bug, which was    +
  (finally!) fixed in SunOS 4.1.2.  If you actually need the full            +
  explanation, send me e-mail.  If you absolutely must compile Emacs 18.55   +
  (eg., you are compiling Nemacs), the easiest workaround was to put         +
  `#define SYSTEM_MALLOC' in src/config.h.                                   +