[plt-dev] Re: [plt] Push #20286: master branch updated

On Sat, May 22, 2010 at 4:47 AM, Eli Barzilay <eli at barzilay.org> wrote:
> On May 21, jay at racket-lang.org wrote:
>> src/foreign/gcc/libffi/src/closures.c
>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> --- OLD/src/foreign/gcc/libffi/src/closures.c
>> +++ NEW/src/foreign/gcc/libffi/src/closures.c
>> @@ -379,8 +379,12 @@ dlmmap_locked (void *start, size_t length, int prot, int flags, off_t offset)
>>         close (execfd);
>>         goto retry_open;
>>       }
>> -      ftruncate (execfd, offset);
>> -      return MFAIL;
>> +       if (ftruncate (execfd, offset)) {
>> +             // FIXME: Should fail "even worse" because the truncate failed
>> +             return MFAIL;
>> +      } else {
>> +         return MFAIL;
>> +       }
>
> Now that I looked at this, it's not clear to me what you're trying to
> get out of this -- you didn't change anything, and since this is C,
> there's no real way to "fail worse" besides segfaulting unless you
> rewrite more code an introduce new special return values etc.

ftruncate is flagged as "warn if return is ignored" on linux, so if
the return is not used there's an annoying error. I don't know what
this code is doing exactly, but presumably it should do "something
different" if the file truncate fails. By inserting the if, the return
is handled and the error is gone.

>> src/gracket/gracket.cxx
>> ~~~~~~~~~~~~~~~~~~~~~~~
>> --- OLD/src/gracket/gracket.cxx
>> +++ NEW/src/gracket/gracket.cxx
>> @@ -19,6 +19,7 @@
>>  /* wx_motif, for wxTimer: */
>>  #ifdef __GNUG__
>>  # pragma implementation "wx_timer.h"
>> +#pragma GCC diagnostic ignored "-Wwrite-strings"
>>  #endif
>
> I get tons of "warning: ignoring #pragma GCC diagnostic" in the build.
> (I haven't looked at which platforms, but it's not a single one.)

That's strange because that's why I put them in __GNUG__. Perhaps it
is only supported by a newer version of GCC?

>> src/gracket/wxs/list.xci
>> ~~~~~~~~~~~~~~~~~~~~~~~~
>> --- OLD/src/gracket/wxs/list.xci
>> +++ NEW/src/gracket/wxs/list.xci
>>  [...]
>> -static Scheme_Object *l_MAKE_LIST(l_TYPE l_POINT *f, l_INTTYPE c)
>> +MAYBE_UNUSED static Scheme_Object *l_MAKE_LIST(l_TYPE l_POINT *f, l_INTTYPE c)
>
> This (and many others) looks suspicious.

Even though Matthew said it's ok. Here's some background: Sometimes
the xc creates lists and vectors that they only traverse (because they
came from other files) but they define the same functions many times,
so gcc complains that you're not using some of the functions you
define.

Jay

-- 
Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University
http://teammccarthy.org/jay

"The glory of God is Intelligence" - D&C 93