"Exception terminator 'invoke' is not supported yet" about rellic HOT 5 CLOSED

I think I'll have to file this one under "won't fix" -- there is no clear way to express the kind of behavior LLVM expects with regards to exception handling in pure C.

from rellic.

Okay, would it be feasible to get rellic to simply ignore (maybe with a message?) a routine it cannot support, while still translating the routines it does?

Right now, if any routine uses invoke, then the whole file cannot be translated; having a “best attempt, sacrificing routines we don’t support” would be very handy.

I'd say it would be feasible but out of scope for Rellic. This would be akin to modifying the bitcode before going into Rellic itself, which is something downstream users should be able to do relatively easily: it's essentially an LLVM pass that goes through every function that contains invoke or landing pads and deletes its body/substitutes it with an unreachable instruction.

Also, should the error message for this one be changed then? It isn’t really “yet” if it won’t ever be supported :)

Heh that's a fair point. I guess it's not really "it won't ever be supported" as much as it is a "we don't know what this looks like yet".

Right now we don't really have an internal use for Rellic anymore so it's not receiving active updates, but if we did want to support exceptions we'd need to think about the fact that there's probably multiple ways to represent them in C (setjmp/longjmp, or maybe straight-up emitting C++) and the users will probably want to have a way to configure Rellic's behavior.

from rellic.

Sure, that wording may be too strong. The GitHub button says "Close as not planned" and I'd say that's the perfect description: we are not planning on implementing this feature in the foreseeable future :)

from rellic.

Okay, would it be feasible to get rellic to simply ignore (maybe with a message?) a routine it cannot support, while still translating the routines it does?

Right now, if any routine uses invoke, then the whole file cannot be translated; having a “best attempt, sacrificing routines we don’t support” would be very handy.

Also, should the error message for this one be changed then? It isn’t really “yet” if it won’t ever be supported :)

from rellic.

Thanks for the feedback, @frabert!

I'd say it would be feasible but out of scope for Rellic.

Okay, understood.

Heh that's a fair point. I guess it's not really "it won't ever be supported" as much as it is a "we don't know what this looks like yet".

Maybe it isn't "won't fix" but more "highly non-trivial and something we're nowhere near addressing" then? That can collide in practical terms with "won't fix", but does actually have a different meaning.

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