Re: FastMM.. any work in progress?

Hi Sanyin,

Can you explain this behaviour?It is not safe to use MMX?

It is safe to use MMX, just not in the memory manager. :-) Some of the "compiler magic" functions pass a floating point parameter on the FPU stack. If such a routine calls the memory manager and the memory manager uses MMX then that FPU parameter will be destroyed, since you cannot use the FPU and MMX at the same time.

So far I have only seen this happen in custom variant code, so admittedly it is rare for this to happen. However, the gain from using MMX is very small (less than 2%), so I decided to play it safe and switch it off by default.

Regards,
Pierre
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