https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113770
--- Comment #8 from Masahide Kashiwagi <kashi at waseda dot jp> --- (In reply to Jakub Jelinek from comment #7) > _Float64x certainly doesn't mean 80-bit. In C, it doesn't have to be > supported at all (such as when IEEE double is the largest type supported by > hw and/or emulation), or can be IEEE quad, 80-bit extended or whatever else. > So, if you need only 80-bit and want an error otherwise, use __float80. Thank you very much. This information was very important to me. I will stop using _Float64x and consider using __float80 or long double.
