https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80154
--- Comment #3 from Daniel Gutson <daniel.gutson at intel dot com> --- Documentation is confusing: -m96bit-long-double -m128bit-long-double These switches control the size of "long double" type. ... -mlong-double-64 -mlong-double-80 -mlong-double-128 These switches control the size of "long double" type. Note that both option families are referred the same in the man page (didn't check the manual). None of these options refer to storage. I guess what I would need is something like -m80bit-long-double. Anyway I suggest to clarify the differences of these two families of options, and if at ever possible, add new ones with more distinct names turning the existing ones obsolete for future versions. In short, please confirm that requiring gcc to store 80-bits precision floating point types into 10 bytes is not possible. Thanks.