On 08/30/2018 10:58 AM, Richard Henderson wrote: > On 08/28/2018 07:13 AM, Jeff Law wrote: >> Please consider using function descriptors rather than trampolines. >> This allows you to make the stack non-executable at all times which is >> good from a security standpoint. The downside is the indirect calling >> mechanism has to change slightly to distinguish between a simple >> indirect call and one through a function descriptor (usually by having a >> low bit on to indicate the latter). GIven this is an ABI change, now is >> probably the last opportunity to make this change. > > Correct me if I'm wrong here: > > Define TARGET_CUSTOM_FUNCTION_DESCRIPTORS to an appropriate value -- easy for > a > RISC target -- and that's it. > > Further, it pretty much only gets used by the Ada front end. One should not > expect these to be used by the C front end nested functions. I thought it was used more extensively than that... Thanks for checking into it though.
Jeff