On Sat, 2020-02-22 at 16:20 +0000, Kyle Evans wrote: > Author: kevans > Date: Sat Feb 22 16:20:04 2020 > New Revision: 358248 > URL: https://svnweb.freebsd.org/changeset/base/358248 > > Log: > vm_radix: prefer __builtin_unreachable() to an unreachable panic() > > This provides the needed hint to GCC and offers an annotation for readers to > observe that it's in-fact impossible to hit this point. We'll get hit with a > a -Wswitch error if the enum applicable to the switch above were to get > expanded without the new value(s) being handled. > > Modified: > head/sys/vm/vm_radix.c > > Modified: head/sys/vm/vm_radix.c > ============================================================================== > --- head/sys/vm/vm_radix.c Sat Feb 22 13:23:27 2020 (r358247) > +++ head/sys/vm/vm_radix.c Sat Feb 22 16:20:04 2020 (r358248) > @@ -208,8 +208,7 @@ vm_radix_node_load(smrnode_t *p, enum vm_radix_access > case SMR: > return (smr_entered_load(p, vm_radix_smr)); > } > - /* This is unreachable, silence gcc. */ > - panic("vm_radix_node_get: Unknown access type"); > + __unreachable(); > } > > static __inline void
What does __unreachable() do if the code ever becomes reachable? Like if a new enum value is added and this switch doesn't get updated? -- Ian _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
