I sense there is a consensus that 1) the 128bit integer is emulated emulated on 64-bit platforms, not available on 32-bit platforms, and is not native anywhere 2) the long long int is 64-bits everywhere so you can *NEVER* do what the document seems to suggest one *MIGHT* be able to do — input a 128-bit constant To me, this would justify rewriting the documentation. My personal lament is that i still cannot find out anywhere if it is available on all 64-bit platforms or on intel only. KS > On Aug 26, 2015, at 3:22 PM, Jonathan Wakely <jwakely.gcc@xxxxxxxxx> wrote: > > On 26 August 2015 at 12:04, Kostas Savvidis wrote: >> The online documentation contains the attached passage as part of the "C-Extensions” chapter. There are no actual machines which have an " integer mode wide enough to hold 128 bits” as the document puts it. > > It's not talking about machine integers, it's talking about GCC > integer modes. Several targets support that. > >> This would be a harmless confusion if it didn’t go on to say “… long long integer less than 128 bits wide” (???!!!) Whereas in reality "long long int” is 64 bits everywhere i have seen. > > > Read it more carefully, it says you can't express an integer constant > of type __int128 on such platforms. > > So you can't write __int128 i = > 999999999999999999999999999999999999999999999999999999999999;
