app-shells/bash-4.3_p39-r1 and possibly older versions breaks shell command line after completion in some situations.

If in bash, start typing

echo /tmp/До<tab>

and substituted text looking weird.
But, if I build bash with
CFLAGS="-march=corei7-avx -mtune=generic -O2 -pipe" instead of "intel64-sandybridge" subarch (CFLAGS="-march=corei7-avx -O2 -pipe"), then everything goes right.