https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85440
--- Comment #20 from Michael Meissner <meissner at gcc dot gnu.org> ---
I'm sorry long double doesn't seem to work on your system. If your system does
not have the appropriate long double libraries, you probably need to use the
--with-long-double-64 option to make long double use the double type. Or you
(or somebody else using the system) need to submit patches, so the compiler
calls whatever is the names of the long double emulation on your system.
With the current compiler, as has been stated, we cannot build libquadmath
unless __float128 is supported. Right now, the only support is for the
following systems:
1) Little endian power8/9 systems
2) Big endian power7/8/9 systems where you use the --with-cpu=<xxx> option,
where <xxx> is power7, power8, or power9.
There just isn't support for a IEEE 128-bit floating point type, unless you
have the VSX (vector scalar extensions) that were first introduced in power7.
The __gcc_q{add,sub,mul,div} come from the libgcc/config/rs6000/ibm-ldouble.c
file. Perhaps it is not configured for your system.
