[Bug target/100049] loop counter double increment with longjmp inside

[clyon at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100049

--- Comment #4 from Christophe Lyon <clyon at gcc dot gnu.org> ---
Actually 'man longjmp' says:

       The compiler may optimize variables into registers, and  longjmp()  may
       restore  the values of other registers in addition to the stack pointer
       and program counter.  Consequently, the values of  automatic  variables
       are  unspecified after a call to longjmp() if they meet all the follow‐
       ing criteria:

       •  they are local to the function that made the corresponding  setjmp()
          call;

       •  their   values  are  changed  between  the  calls  to  setjmp()  and
          longjmp(); and

       •  they are not declared as volatile.

In this case, "i" is not modified between setjmp() and longjmp(), but it seems
the compiler moves the increment between them.