On Sunday, 17 June 2018 at 10:58:29 UTC, Cauterite wrote:
Hello,
I'm not sure whether I'm missing something obvious here, but is
there a reason for scope(success) being lowered to a try-catch
statement?
I would have expected only scope(exit) and scope(failure) to
actually interact with exception handling, while scope(success)
simply places code on the path of normal control flow.
Example (windows x32):
---
// main.d
void main() {
scope(success) {}
}
dmd -betterC main.d
Error: Cannot use try-catch statements with -betterC
---
Regardless of whether -betterC is used, you can see in the
disassembly that having a scope(success) anywhere in the
function causes the SEH prologue to be emitted in the code.
Is there a reason scope(success) needs to set up for exception
handling?
Or is this a bug / potential enhancement ?
I suspect scope(success) is lowered because scope(exit) and
scope(failure)
are, and that would result in a simpler (compiler) implementation
of it.
does adding nothrow to main fix it? For dcompute I specifically
allow scope(exit|success) because there will never be any
exceptions _at all_.
If not, please do submit an issue. Also a better error message
should be given.
