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Comment by charcircuit | Hacker News Reader

>The workaround for this is to cripple the system

That is not the workaround in the documentation that was just linked.

  Workarounds:
  The solution to this problem is to put two instructions that do not require write back data after the mul instruction.

This seems reasonable for your compiler vendor to implement without getting rid of multiplication altogether.

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There's a difference in effort of several orders of magnitude between "change a setting so the compiler doesn't emit multiplies" and "convince GCC/LLVM to add a special-case flag for one very rare chip, or maintain your own fork". The vendor's workaround is the "ideal" solution, but disabling multiplies is a lot more practical if you don't need the performance.

They also mention in the next sentence that they adopted the "correct" workaround (by providing a multiplication library function for the compiler to call).

The company selling the chip can create a fork. They are typically the ones providing all of the sdks for you to use in order to use it, flash it, debug it, etc.

even if you don't know which instructions they are, just place two nops after every mul, problem solved

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