A warning found during GCC 6.1.0 compilation process (may be a critical error or bug)

[Ethin Probst <harlydavidsen at gmail dot com>]

Hello GCC developers and GCC mailing list members:
This message concerns some warnings noted by GCC during the
compilation of GCC 6.1.0. If GCC had the -Werror flag passed, this
would be an error. I'm not sure if this is an error, just a warning
that I should ignore, or a bug, but I just wanted you to note the
following warning:
In file included from ../../gcc/rtl.h:34,
                 from ../../gcc/genpreds.c:27:
../../gcc/vec.h: In static member function âstatic size_t vec<T, A,
vl_embed>::embedded_size(unsigned int) [with T = std::pair<unsigned
int, const char*>, A = va_heap]â:
../../gcc/vec.h:286:   instantiated from âstatic void
va_heap::reserve(vec<T, va_heap, vl_embed>*&, unsigned int, bool)
[with T = std::pair<unsigned int, const char*>]â
../../gcc/vec.h:1406:   instantiated from âbool vec<T, va_heap,
vl_ptr>::reserve(unsigned int, bool) [with T = std::pair<unsigned int,
const char*>]â
../../gcc/vec.h:1515:   instantiated from âT* vec<T, va_heap,
vl_ptr>::safe_push(const T&) [with T = std::pair<unsigned int, const
char*>]â
../../gcc/genpreds.c:1524:   instantiated from here
../../gcc/vec.h:1026: warning: invalid access to non-static data
member âvec<std::pair<unsigned int, const char*>, va_heap,
vl_embed>::m_vecdataâ  of NULL object
../../gcc/vec.h:1026: warning: (perhaps the âoffsetofâ macro was used
incorrectly)
There are many other warnings, and I will post a link to the
compilation logs when the compilation finishes. (I've had to redo the
compilation more than once because SSH decided to idle timeout and
make noted the hangup, ending the compilation process immediately due
to there being no TTY to send messages to, even though I'd had them
(and still have them) redirected to a file.)
-- 
Signed,
Ethin D. Probst