[Bug target/84772] powerpc-spe: Spurious "is used uninitialized" warning, or possibly incorrect codegen for va_arg(long double)

[zackw at panix dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84772

--- Comment #4 from Zack Weinberg <zackw at panix dot com> ---
The last actual _change_ in my GCC build is

r258315 | denisc | 2018-03-07 04:13:12 -0500 (Wed, 07 Mar 2018) | 9 lines

        Backport from mainline
        2018-02-07  Georg-Johann Lay  <avr@gjlay.de>

        PR target/84209
        * config/avr/avr.h (GENERAL_REGNO_P, GENERAL_REG_P): New macros.
        * config/avr/avr.md: Only post-reload split REG-REG moves if
        either register is GENERAL_REG_P.