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0 pointsraw_anon_11112mo ago0 comments

That sounds like the same ugly hack that caused programs not to be “32 bit clean” back in the day for Macs

0 comments

One difference is that the Mac OS itself was not initially 32-bit clean, with the top byte being used by the Memory Manager.

rwmj2mo ago

Ah yes, these 68000 pointers have a spare 8 bits for me to use! Because nothing will ever need more than 16 MB of memory. Sigh.

It's all good if you have 128kb ram but they should have had a plan to escape it from day one.

dcrazy2mo ago

This is how pointer authentication codes work on Arm64.

j / k navigate · click thread line to collapse

One difference is that the Mac OS itself was not initially 32-bit clean, with the top byte being used by the Memory Manager.

rwmj2mo ago

Ah yes, these 68000 pointers have a spare 8 bits for me to use! Because nothing will ever need more than 16 MB of memory. Sigh.

It's all good if you have 128kb ram but they should have had a plan to escape it from day one.

dcrazy2mo ago

This is how pointer authentication codes work on Arm64.

j / k navigate · click thread line to collapse