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Re: Serious code generation/optimisation bug (I think)


On Jan 27, 2009, at 1:10 PM, Ian Lance Taylor wrote:

Laurent GUERBY <laurent@guerby.net> writes:

Just curious: is there a "portable" way to read from memory
address zero in C code? "portable" here means likely to work
on most compilers without exotic compile flags in 2009.


char *my_null_pointer;
char fn() { return *my_null_pointer; }

It will be quite a while before whole program optimization is good
enough to prove that my_null_pointer is not referenced by anything
else.

Perhaps in GCC, but this is not a good solution if you care about other compilers.

-Chris

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