[LLVMdev] Is LLVM expressive enough to represent asynchronous exceptions?

[Duncan Sands]

Hi Chris,

> While a european vacation sounds nice, I don't think that support for asynch exceptions is desirable in LLVM.  Synchronous exceptions like divide by zero or null pointer derefs are another thing entirely though.

as I mentioned in a reply to another email in this thread, Ada does make use of
asynchronous exceptions.  However support for this does not have to be great: if
such an exception occurs then you are already fairly far into "nasal demon"
territory as far as the Ada language is concerned, and I'm pretty sure that as
far as Ada is concerned the optimizers can ignore this possibility.  The GCC Ada
front-end does not rely on traps for catching division by zero and such: it
inserts explicit checks (presumably because it is too hard to preserve correct
semantics otherwise, or perhaps GCC's trap support doesn't work reliably).

Ciao, Duncan.