gccjit::context::get_first_error documented but not implemented

[Marc Nieper-Wißkirchen]

The method

gccjit::context
<https://gcc.gnu.org/onlinedocs/jit/cp/topics/contexts.html#_CPPv3N6gccjit7contextE>
::get_first_error

is documented ([1]), but a search in libgccjit++.h reveals no
implementation.

--

[1]
https://gcc.gnu.org/onlinedocs/jit/cp/topics/contexts.html#_CPPv3N6gccjit7context15get_first_errorEPN6gccjit7contextE