[Bug target/85805] Improper code generation for 64 bit comparisons on avr-gcc

[sandor.zsuga at jubatian dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85805

--- Comment #5 from Sandor Zsuga <sandor.zsuga at jubatian dot com> ---
I received a test report with avr-gcc 8.1.0 , -O2 optimization level: The
behavior is present ( https://www.avrfreaks.net/comment/2477081#comment-2477081
).