[Libguestfs] Note regarding bin2s.pl

[Richard W.M. Jones]

On Tue, Jan 12, 2016 at 07:57:03AM +0100, Hilko Bengen wrote:
> Helge,
> 
> I have applied all the architecture-specific bits but not the bin2s
> script yet. TBH, so far I don't see what is wrong about export and use
> of the "_binary_init_size" constant.

[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=809185]

I see it as a reasonable simplification - it allows us to get rid of
that conditional code for HP-UX in bin2s.pl.

However looking at the patch, I don't like the casts in:

-  size_t n = (size_t) &_binary_init_size;
+  size_t n = ((size_t) &_binary_init_end) - ((size_t) &_binary_init_start);

Since those are pointers, it seems better to simply subtract them.
(Though it would be better if we'd declared the type of
_binary_init_start/_end as uint8_t instead of char.)

If we must cast them then the correct integer to use is 'intptr_t', an
int type that's guaranteed by C99 to be long enough to store a
pointer.

Rich.

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