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

ZoltÃn KÃcsi wrote: 
On Thu, 29 Jan 2009 08:53:10 +0000
Andrew Haley <aph@redhat.com> wrote:

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.


Um, the linker *must* place the vector table at address zero, because
the ARM, at least the ARM7TDMI fetches all exception vectors from
there. Dictated by the HW, not the compiler.

This sounds like a genuine bug in gcc, then. As far as I can see, Andrew is right -- if the ARM hardware requires a legitimate object to be placed at address zero, then a standard C compiler has to use some other value for the null pointer.

-- Ross Smith

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