Re: system.h cleanups

[Jim Meyering]

Pádraig Brady wrote:
> Jim Meyering wrote:
>> Eric Blake wrote:
>>> >From 3fe95b8d5294df9747982cc6e41a6adb621450a0 Mon Sep 17 00:00:00 2001
>>> From: Eric Blake <address@hidden>
>>> Date: Thu, 8 Oct 2009 08:10:50 -0600
>>> Subject: [PATCH 2/3] maint: remove unused macros and declarations
>>>
>>> * src/system.h (strdupa): Delete unused macro.
>> ...
>>> -# define ASSIGN_STRDUPA(DEST, S)           \
>>> -  do { DEST = strdupa (S); } while (0)
>>> -#else
>>> -# define ASSIGN_STRDUPA(DEST, S)           \
>>> -  do                                               \
>>> -    {                                              \
>>> -      const char *s_ = (S);                        \
>>> -      size_t len_ = strlen (s_) + 1;               \
>>> -      char *tmp_dest_ = alloca (len_);             \
>>> -      DEST = memcpy (tmp_dest_, s_, len_); \
>>> -    }                                              \
>>> -  while (0)
>>> -#endif
>> ...
>>
>> ??  As far as I can see, one cannot remove ASSIGN_STRDUPA,
>> since it is not defined anyplace else.
>> The code (cp.c, df.c, copy.c) won't compile without it.
>
> As a side note removing it will allow reinstating a warning check:
> http://lists.gnu.org/archive/html/bug-coreutils/2009-07/msg00069.html

Perhaps it compiled for Eric because he was building
with some patch that removes all of those uses?

I think I've audited all of those at one time or another.
I haven't been very concerned with the one in copy.c,
because as a comment there probably says, the offending
use will go away with the fts rewrite.  Besides, given
existing PATH_MAX limitations, it's relatively hard to
trigger bad behavior.

All that said, if anyone wants to take the time to
cleanly replace those (no exit, no leaks allowed), please do.