Date: Thu, 17 Mar 2016 13:04:37 -0700 From: Gleb Smirnoff <glebius@FreeBSD.org> To: Hans Petter Selasky <hps@selasky.org> Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r296933 - in head: share/man/man9 sys/sys Message-ID: <20160317200437.GW1328@FreeBSD.org> In-Reply-To: <56EA5A96.5070402@selasky.org> References: <201603160837.u2G8bqgr087126@repo.freebsd.org> <20160316203601.GO1328@FreeBSD.org> <56EA5A96.5070402@selasky.org>
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On Thu, Mar 17, 2016 at 08:19:50AM +0100, Hans Petter Selasky wrote: H> On 03/16/16 21:36, Gleb Smirnoff wrote: H> > On Wed, Mar 16, 2016 at 08:37:52AM +0000, Hans Petter Selasky wrote: H> > H> Modified: head/sys/sys/sysctl.h H> > H> ============================================================================== H> > H> --- head/sys/sys/sysctl.h Wed Mar 16 06:42:15 2016 (r296932) H> > H> +++ head/sys/sys/sysctl.h Wed Mar 16 08:37:52 2016 (r296933) H> > H> @@ -654,8 +654,10 @@ TAILQ_HEAD(sysctl_ctx_list, sysctl_ctx_e H> > H> SYSCTL_OID(parent, nbr, name, \ H> > H> CTLTYPE_OPAQUE | CTLFLAG_MPSAFE | (access), \ H> > H> (ptr), (len), sysctl_handle_counter_u64_array, "S", descr); \ H> > H> - CTASSERT(((access) & CTLTYPE) == 0 || \ H> > H> - ((access) & SYSCTL_CT_ASSERT_MASK) == CTLTYPE_OPAQUE) H> > H> + CTASSERT((((access) & CTLTYPE) == 0 || \ H> > H> + ((access) & SYSCTL_CT_ASSERT_MASK) == CTLTYPE_OPAQUE) && \ H> > H> + sizeof(counter_u64_t) == sizeof(*(ptr)) && \ H> > H> + sizeof(uint64_t) == sizeof(**(ptr))) H> > H> > I don't agree with the last line. Does it assert that counter_u64_t is H> > implemented using uint64_t? That is true, but that is internal detail, H> > that might be changed in future. H> > H> H> Yes, it asserts that counter_u64_t is a 64-bit counter, as the name of H> the typedef hints at. H> H> From the past experience there has been several cases where someone has H> changed a field in structure which is exported as a sysctl, and then the H> sysctls were never updated. It could be that counter_u64_t becomes a machine dependent typedef, being different size on different machines. Unlikely, but possible. -- Totus tuus, Glebius.
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