I'm trying to implement a custom exception system in BetterC. Does anyone know how I'd go about getting a stack trace so that I can print it to stdout? :)
I was thinking of utilising UDAs & __LINE__ but it turns out that UDAs don't let you inject code, which is a shame!

On Sunday, 4 September 2022 at 17:43:01 UTC, IchorDev wrote:

You can use libunwind for this:

https://www.nongnu.org/libunwind/

It's a C library, but it should work for D too.

On Sunday, 4 September 2022 at 18:49:37 UTC, Paul Backus wrote:

Ah, I'm actually trying to create my own implementation of this, so the goal would be to not rely on a dependency.
I can't exactly make head nor tail of the library's source other than that it seems to have a unique implementation on each processor/OS type.

I'm sure there must be something hidden in core.internal. for this. I'll look at the implementation of rt.trace and see if I can find anything.

On Monday, 5 September 2022 at 10:47:38 UTC, IchorDev wrote:

I think this is what you are looking for:

https://github.com/dlang/dmd/blob/master/druntime/src/rt/deh.d

On Monday, 5 September 2022 at 12:07:35 UTC, Paul Backus wrote:

Digging in a little deeper, it looks like the druntime implementation ultimately depends on the C++ exception handling ABI, via its platform-independent library interface. Bindings are defined in core.internal.backtrace.unwind.

There is also what looks like a from-scratch implementation of table-based exception handling in rt.deh_win64_posix, but according to a comment it is no longer used. Might be educational to read, though.

On Monday, 5 September 2022 at 12:35:10 UTC, Paul Backus wrote:

It even uses libunwind, it seems! https://github.com/dlang/dmd/blob/master/druntime/src/core/internal/backtrace/handler.d
Thanks for the pointers, too. :)