On 2016-04-13 13:32:13 -0700, Kevin J. McCarthy wrote:
> Is casting a size_t to a (signed) implementation defined or undefined?
implementation defined
> Is it a problem to then divide that by an int and assign the result to
> an int?
Note that "signed" is just a synonymous for "int".
> Are we forced to write something like:
>
> /* try to consume as many columns as we can, if we don't have
> * memory for that, use as much memory as possible */
> if (wlen + (pad * pl) + len > destlen)
> if (wlen + len > destlen)
> pad = 0;
> else
> pad = (destlen - wlen - len) / pl;
> else
You could write it:
if (wlen + (pad * pl) + len > destlen)
pad = wlen + len > destlen ? 0 : (destlen - wlen - len) / pl;
else
to avoid the not so readable nested if's.
> > And the division with a negative argument is only defined in C99,
> > so that may be another problem (it is known that some compilers may
> > still deviate from C99, including GCC unless -std=c99 is provided).
>
> Fortunately, we do have AC_PROG_CC_C99 in our configure.ac now.
So, division with negative arguments should be OK.
Note that instead of using the type size_t, you can probably use the
type long, to avoid the problem with the cast.
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Vincent Lefèvre <[email protected]> - Web: <https://www.vinc17.net/>
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