On Wed, 08 Jan 2020 18:33:40 PST (-0800), richard.hender...@linaro.org wrote:
On 1/9/20 11:49 AM, Palmer Dabbelt wrote:
+ irqs = (pending & ~env->mideleg & -mie) | (pending & env->mideleg & -sie);
Isn't "-unsigned" implementation defined? I can't get GCC to throw a warning
and it was already there, so maybe I'm just wrong?
(1) You're confusing implementation defined with undefined, and unsigned
arithmetic is the former not the latter.
(2) There is no such thing as ones-compliment or sign-magnitude integer
hardware anymore, so for this case "implementation defined" is in fact
universal.
(3) We build with -fwrapv, so we're explicitly asking for sane behaviour from
our signed types as well.
Ah, thanks -- I didn't know we had -fwrapv. In that case we're safe!
r~
