* cygwin.din (sys_sigabbrev): Add this here.

* cygwin.din (sys_sigabbrev): Add this here.
* dcrt0.cc (__argc,__argv,_check_for_executable): Remove dllexport decoration
since it is already handled in cygwin.din.
* errno.cc (_sys_errlist): Ditto.
* strsig.cc (sys_sigabbrev): Ditto.
* include/cygwin/signal.h: Protect use of dllimport when __INSIDE_CYGWIN__.
* libc/getopt.c: Revert previous changes.  Define __INSIDE_CYGWIN__.