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Although this > might not be controversial and be sorted by the time Plumbers happens. I guess this one is levied at me. Hopefully it isn't controversial in any way.=C2=A0 I have just had sufficie= nt tuits to get around to making an x86 straight line speculation feature request to the GCC and Clang communities yet. For the compiler folk here, the tl;dr is that indirect CALL/JMP (i.e. function pointers, jump tables) and RET instructions may speculatively execute the next sequential instruction(s) before taking the control flow change into account.=C2=A0 Having some toolchain support to deal with this would be great, and preferable to some of the asm hackary currently under suggestion. ~Andrew