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Re: Null pointer check elimination
Gabriel Dos Reis wrote:
"Michael N. Moran" <mike@mnmoran.org> writes:
| Wow. I'm sure there is sound reasoning for this ... but I can't
| understand what that might be given a client module could intentionally
| (if ill-adviseadly) simply invoke the function:
then it gets what it deserves. Check out GCC manual for null-pointer
check.
From info gcc:
`-fdelete-null-pointer-checks'
Use global dataflow analysis to identify and eliminate useless
checks for null pointers. The compiler assumes that dereferencing
a null pointer would have halted the program. If a pointer is
checked after it has already been dereferenced, it cannot be null.
The second sentence makes me question the difference between an
actual dereferencing operation and the use of a dereferencing
operator used to convert a pointer to a C++ reference. Clearly
(to me anyway ;-) the conversion case does not actually cause
an access to the object.
--
Michael N. Moran (h) 770 516 7918
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