Date: Fri, 19 Jan 2018 10:31:32 -0800 From: Conrad Meyer <cem@freebsd.org> To: John Baldwin <jhb@freebsd.org> Cc: src-committers <src-committers@freebsd.org>, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r328159 - head/sys/modules Message-ID: <CAG6CVpVSjSbOwM=ktSJAjfapVNTFeNpnfZ1tMy-2-MKu9Rsmuw@mail.gmail.com> In-Reply-To: <2915608.v56yfz43Ej@ralph.baldwin.cx> References: <201801190434.w0J4Y6i7086677@repo.freebsd.org> <2915608.v56yfz43Ej@ralph.baldwin.cx>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, Jan 19, 2018 at 9:51 AM, John Baldwin <jhb@freebsd.org> wrote: > On Friday, January 19, 2018 04:34:06 AM Conrad Meyer wrote: >> The logical result of a right shift >=3D the width of a type is zero, = but our >> compiler decides this is a warning (and thus, error). Just remove ccp= (4) >> from i386. > > You would think that. The shift instructions on x86 effectively ignore t= he > upper bits of the count, so a 33-bit shift on i386 ends up being a 1-bit = shift, > etc. IIRC. This never becomes a shift instruction on x86 or any other arch =E2=80=94 i= t's a constant before it reaches machine code.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAG6CVpVSjSbOwM=ktSJAjfapVNTFeNpnfZ1tMy-2-MKu9Rsmuw>