https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99197
Michael Meissner <meissner at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |meissner at gcc dot gnu.org Resolution|--- |FIXED Status|UNCONFIRMED |RESOLVED --- Comment #1 from Michael Meissner <meissner at gcc dot gnu.org> --- These functions have been documented since June 2018. The file extend.texi contains: The @code{__builtin_unpack_ibm128} function takes a @code{__ibm128} argument and a compile time constant of 0 or 1. If the constant is 0, the first @code{double} within the @code{__ibm128} is returned, otherwise the second @code{double} is returned. The @code{__builtin_pack_ibm128} function takes two @code{double} arguments and returns a @code{__ibm128} value that combines the two arguments.