On Jun 25, 2012, at 10:26 AM, Steven Bosscher wrote:
> On Mon, Jun 25, 2012 at 9:13 AM, Eric Botcazou <ebotca...@libertysurf.fr>
> wrote:
>>> The PA and SPARC back ends do not define DONT_USE_BUILTIN_SETJMP, so
>>> they also do not have to define JMP_BUF_SIZE. So:
>>>
>>> * config/sparc/sparc.h (JMP_BUF_SIZE): Do not define.
>>> * config/pa/pa.h (JMP_BUF_SIZE): Likewise.
>>>
>>> OK for trunk?
>>
>> OK for the SPARC, thanks.
>
> And thanks to you for the ack! :-)
>
>> What about the Stormy16 and the picoChip? It seems
>> like a cleanup is possible in this area for them as well.
>
> Right, I didn't look at the details of the uses of
> DONT_USE_BUILTIN_SETJMP and JMP_BUF_SIZE but it looks like the ones in
> picochip and stormy16 are redundant too:
>
> For picochip, this port defines DONT_USE_BUILTIN_SETJMP but in the .c
> file (and after all #includes), so it is never exported and not
> otherwise referenced in picochip.c, hence dead:
> config/picochip/picochip.c:#undef DONT_USE_BUILTIN_SETJMP
> config/picochip/picochip.c:#define DONT_USE_BUILTIN_SETJMP 1
>
> stormy16 only undefines DONT_USE_BUILTIN_SETJMP (which is the default
> anyway) so these two lines are redundant:
> config/stormy16/stormy16.h:#undef DONT_USE_BUILTIN_SETJMP
> config/stormy16/stormy16.h:#define JMP_BUF_SIZE 8
>
> I will remove those lines with the same commit.
>
> That leaves only rl78 and ia64:
> $ egrep "DONT_USE_BUILTIN_SETJMP|JMP_BUF_SIZE" config/* config/*/*
> config/ia64/freebsd.h:#define JMP_BUF_SIZE 76
> config/ia64/hpux.h:#define JMP_BUF_SIZE (8 * 76)
> config/ia64/ia64.h:#define DONT_USE_BUILTIN_SETJMP
> config/ia64/linux.h:#define JMP_BUF_SIZE 76
> config/ia64/vms.h:#define JMP_BUF_SIZE (8 * 76)
> config/rl78/rl78.h:/*#define DONT_USE_BUILTIN_SETJMP 1*/
> config/rl78/rl78.h:#undef DONT_USE_BUILTIN_SETJMP
> config/rl78/rl78.h:#define JMP_BUF_SIZE (8*3+8)
>
> The ia64 ones have no useful comments. The 76 is a magic number and it
> seems strange to me that the size of JMP_BUF_SIZE depends on the OS
> (linux and freebsd have 76, hpux has 8*76, and vms copied the hpux
> example with the comment: "Maybe same as HPUX? Needs to be
> checked."). And anyway, these macros are only relevant for SJLJ
> exceptions - who uses that on ia64??
FTR, until recently I think it was not possible to use SJLJ on ia64 due to a
typo.
On hpux, the definition of jmp_buf is:
# define _JBLEN 320
typedef __float80 jmp_buf[_JBLEN/4];
which looks weird...
Tristan.
