* libc/include/machine/setjmp.h (siglongjmp): Declare as function on
Cygwin.
(sigsetjmp): Ditto.
(_longjmp): Mark as noreturn function on Cygwin.
* common.din (siglongjmp): Export.
(sigsetjmp): Export.
* gendef: Change formatting of some comments.
(sigsetjmp): Implement.
(siglongjmp): Implement.
(__setjmpex): x86_64 only: Drop entry point.
(setjmp): x86_64 only: Store tls stackptr in Frame now, store MXCSR
and FPUCW registers in Spare, as MSVCRT does.
(longjmp): x86_64 only: Restore tls stackptr from Frame now, restore
MXCSR and FPUCW registers from Spare.
* include/cygwin/version.h (CYGWIN_VERSION_API_MINOR): Bump.
* new-features.xml (ov-new2.2): Document sigsetjmp, siglongjmp.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>