Hi Richard, On Sat, 2018-01-06 at 11:27 +0000, Richard W.M. Jones wrote: > I noticed as a side effect of compiling GCC for riscv64 that RISC-V's > GCC doesn't support -fstack-clash-protection. Do you know what is > involved to add it? From a naive point of view I don't understand > why this feature depends on architecture at all. Sorry, I don't know the precise details on the gcc side. I believe it is architecture dependent because it depends on the exact calling conventions and how specific call instructions that manipulate the stack. gcc wants the stack probes to be as efficient as possible. So it only explicitly lowers the stack and inserts probes if absolutely necessary. That is also why there were originally subtle issues around no-return functions (because their calling conventions are different and so gcc couldn't rely on the stack pointer already being lowered and/or arguments having been pushed on it already). Cheers, Mark _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx
