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

Erik Trulsson wrote:
> On Wed, Jan 28, 2009 at 04:39:39PM +0000, Andrew Haley wrote:

>> "6.3.2.3 Pointers
>>
>> If a null pointer constant is converted to a pointer type, the
>> resulting pointer, called a null pointer, is guaranteed to compare
>> unequal to a pointer to any object or function."
>>
>> This implies that a linker cannot place an object at address zero.
> 
> Wrong.  There is nothing which requires a null pointer to be all-bits-zero
> (even though that is by far the most common representation of null
> pointers.)

We're talking about gcc on ARM.  gcc on ARM uses 0 for the null pointer
constant, therefore a linker cannot place an object at address zero.
All the rest is irrelevant.

Andrew.
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