Can't always turn optimizers off [LWN.net]

Can't always turn optimizers off

Posted Apr 26, 2018 11:42 UTC (Thu) by wittenberg (guest, #4473)
In reply to: Security quotes of the week by mjthayer
Parent article: Security quotes of the week

Even with optimization turned off, some compilers do some optimization anyway. It's really hard to find a way to get the compiler to do what you told it to do.

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Can't always turn optimizers off

Posted Apr 26, 2018 12:29 UTC (Thu) by excors (subscriber, #95769) [Link] (2 responses)

Even if the compiler does what you told it to do, Spectre demonstrates that the CPU won't do what the compiler told it to do. Maybe we need to give up on the idea of implementing timing-attack-safe cryptographic primitives in software, and do it all in hardware instead.

Can't always turn optimizers off

Posted Apr 26, 2018 14:48 UTC (Thu) by mrshiny (guest, #4266) [Link] (1 responses)

"the CPU won't do what the compiler told it to" proves that you can't always do it in hardware either.

Can't always turn optimizers off

Posted Jun 7, 2018 1:34 UTC (Thu) by JanC_ (subscriber, #34940) [Link]

Especially as fixing the hardware is often not possible (or at least requires hardware vendor intervention).