Re: codecvt problem
On 2011-06-20 12:16, Ulrich Eckhardt wrote:
Seungbeom Kim wrote:
On 2011-06-17 05:42, Ulrich Eckhardt wrote:
This means that all "clean" initialisations
mentioned in this thread (e.g. "mbstate_t s = {};" or "mbstate_t s =
mbstate_t();") are actually not guaranteed to work.
I cannot understand why not. Can you explain it further?
1. a null pointer doesn't have to have all its bits zero
2. memset(&ptr, 0, sizeof ptr) only guarantees that all bits are zero, but
not that 'ptr' becomes a null pointer
3. above mentioned "clean" initialisations of pointers yield null pointers
With that, assuming the spec requires an initialisation with memset(),
other
initialisations where a pointer might become a null pointer are actually
not
portable, because they give a different result.
I see your point. I highly doubt that such implementations that ask
users to use memset will not work with real null pointers produced by
"clean" initialisations; i.e. I expect that they are based on the
assumption, or guarantee, that memset does produce a real null pointer;
i.e. that a null pointer is all-bits-zero.
--
Seungbeom Kim
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