On Tuesday, May 19, 2015 12:28:05 AM Pedro Giffuni wrote: > >>>> Modified: head/sys/ddb/db_break.c > >>>> ============================================================================== > >>>> --- head/sys/ddb/db_break.c Mon May 18 22:14:06 2015 > >>>> (r283087) > >>>> +++ head/sys/ddb/db_break.c Mon May 18 22:27:46 2015 > >>>> (r283088) > >>>> @@ -155,12 +155,12 @@ db_find_breakpoint_here(db_addr_t addr) > >>>> return db_find_breakpoint(db_map_addr(addr), addr); > >>>> } > >>>> > >>>> -static boolean_t db_breakpoints_inserted = TRUE; > >>>> +static boolean_t db_breakpoints_inserted = true; > >>> > >>> This code hasn't been churned to use the boolean type. It still uses > >>> boolean_t, which is plain int. TRUE and FALSE go with this type. true > >>> and false go with the boolean type. This probably makes no difference, > >>> because TRUE happens to be implemented with the same value as true and > >>> there are lots of implicit versions between the types. > >> > >> Yes, I noticed the return types are still ints. It doesn’t look difficult > >> to convert it to use a real boolean type. In any case, I would prefer to > >> go > >> forward (using bool) instead of reverting this change. > > > > That wuld be sideways. > > > > I forgot to mention (again) in my previous reply that boolean_t is a mistake > > by me. KNF code doesn't even use the ! operator, but uses explicit > > comparison with 0. The boolean_t type and TRUE and FALSE are from Mach. > > They were used mainly in ddb and vm, and are still almost never used in > > kern. I used to like typedefs and a typedef for boolean types, and didn't > > know KNF very well, so in 1995 I moved the declaration of boolean_t from > > Mach vm code to sys/types.h to try to popularize it. This was a mistake. > > Fortunately, it is still rarely used in core kernel code. > > > > The boolean type is also almost never used for syscalls. In POSIX.1-2001, > > <stdbool.h> is inherited from C99, but is never used for any other POSIX > > API. Using it for syscalls would mainly cause portability problems. > > > > OK, I do understand the kernel wants to keep the C dialect somewhat limited, > and adding stdbool.h doesn’t buy us any type safety here. > > I’ll revert the change (prob. tomorrow though).
I will disagree with Bruce a bit and put my vote in for replacing boolean_t with bool where it is used. I do think that logically (if not strictly) your commit is a type mismatch as TRUE/FALSE is for boolean_t and true/false are for bool. I agree with Bruce that we probably don't want to use bool for system calls. However, I think using bool in the kernel itself is ok and that we should replace boolean_t with bool. -- John Baldwin _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
