https://sourceware.org/bugzilla/show_bug.cgi?id=32813
--- Comment #4 from Andreas Abel <abel at cs dot uni-saarland.de> --- With respect to performance, the processor behaviors are not identical. The one with an 64-bit operand size is one byte longer, which can have various effects on performance. Yes, I could add workarounds to my code, but it would be preferable if this could be fixed at the source. Earlier versions of gas correctly added the REX prefix, and other assemblers (I tested nasm and XED) also encode this correctly with a REX prefix. -- You are receiving this mail because: You are on the CC list for the bug.
