[Bug c/59039] Undocumented __builtin_longjmp/__builtin_setjmp

[gcc at kalvdans dot no-ip.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59039

--- Comment #31 from Christian Häggström <gcc at kalvdans dot no-ip.org> ---
What you describe Sandra is mentioned in the man page for longjmp(3). Maybe we
can steal some of its documentation.

   Caveats
       If  the  function  which  called  setjmp()  returns before longjmp() is
       called, the behavior is undefined.  Some kind  of  subtle  or  unsubtle
       chaos is sure to result.