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From: "aklauer at rumms dot uni-mannheim.de" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c/45779] pointer difference error/ptrdiff_t representability
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45779

--- Comment #1 from Alexander <aklauer at rumms dot uni-mannheim.de> 2010-09-27 16:20:48 UTC ---
While fiddling around a bit more I found that gcc normally doesn't let me
create objects whose size exceeds PTRDIFF_MAX. For objects of size at most
PTRDIFF_MAX, the bug cannot be triggered. The only function I found which does
create such large objects is malloc(). Presumably, its companions calloc() and
realloc() do so as well.

In this light, the best fix for this bug seems to be for malloc() and
companions to simply return NULL upon a request for an object whose size
exceeds PTRDIFF_MAX.