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[Bug c/49595] on amd64, sizeof(__int128_t) > sizeof(intmax_t)
- From: "sandals at crustytoothpaste dot net" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Thu, 30 Jun 2011 18:12:41 +0000
- Subject: [Bug c/49595] on amd64, sizeof(__int128_t) > sizeof(intmax_t)
- Auto-submitted: auto-generated
- References: <bug-49595-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49595
--- Comment #3 from brian m. carlson <sandals at crustytoothpaste dot net> 2011-06-30 18:12:39 UTC ---
(In reply to comment #2)
> sizeof(intmax_t) is fixed by various LP64 ABIs and cannot be changed
That does sound potentially problematic. I don't see how that solves the
standard conformance issue, though. If intmax_t cannot be changed, then I
suppose the only appropriate behavior is not to provide any integer types
larger
than intmax_t with -std=c99.
> I believe the stock answer is that __int128 is not a C99 extended integer type,
> so isn't one of the types that intmax_t can represent the value of
There are five *standard signed integer types*.... There may also be
*implementation-defined extended signed integer types*. The standard and
extended signed integer types are collectively called *signed integer types*.
Since the standard specifies intmax_t in terms of a "signed integer type", it
therefore includes any implementation-defined extended signed integer types,
including __int128_t.