Edit & Continue (EnC) support for Linux and macOS

[uwu-420]

Hello!

I just saw that for Windows, netcoredbg actually supports Edit & Continue (supercharged hot reload basically) and I wonder if it's planned to add this functionality also for Linux and macOS.

I think that this would be a welcome improvement as more and more people rely on netcoredbg for debugging C# code on these platforms with IDEs/editors like VSCode forks, Zed, Neovim or Helix which cannot use vsdbg.

https://github.com/Samsung/netcoredbg/blob/8b8b22200fecdb1aec5f47af63215462d8c79a4b/clrdefinitions.cmake#L105C1-L109C67

[viewizard]

Hello,

At this moment netcoredbg support Hot Reload feature only for Tizen OS (that have runtime build with this feature enabled), plus, can be used only with MSVS Tizen plugin (that will track source changes and generate for debugger deltas/diffs to apply), only MI/GDB protocol in netcoredbg support this additional not standard commands now.

So, this is 2 parts you need - Linux/macOS runtime build with EnC/Hot Reload enabled (debugger interface should have EnC part compiled, or methods will be unavailable) and some IDE that will generate deltas (metadata, IL code and PDB changes of code).

Example of IDE part work (deltas generation) you could see in our tests:
https://github.com/Samsung/netcoredbg/tree/master/test-suite/NetcoreDbgTest/Delta

Code you linked don't used in debugger build, initially coreclr cmake files were used, so, it don't reflect debugger's Hot Reload feature status.
Hot Reload feature could be enabled by NCDB_DOTNET_STARTUP_HOOK:
https://github.com/search?q=repo%3ASamsung%2Fnetcoredbg%20NCDB_DOTNET_STARTUP_HOOK&type=code

Frankly speaking, I don't think that ppl ready build custom runtime for Linux/macOS and someone will implement tracking for source changes and deltas generation... netcoredbg itself is ready for any OSes usage, no limits here.

[MattParkerDev]

Hi @viewizard, are you saying that the official .NET SDK on Linux and macOS is not compiled with EnC support? Ie that Rider supplies a custom SDK on Unix?

[viewizard]

Hmmm, just checked upstream sources and looks like runtime have enabled EnC for arm64 and amd64 for all OSes now:
https://github.com/dotnet/runtime/blob/abe8e17a3b9f518844dabb54c88e9b70133fa0fc/src/coreclr/clrdefinitions.cmake#L55-L57
looks like I missed this one (was not pay attention on this part after we finished Hot Reload in netcoredbg, sorry about that), here is the commit
dotnet/runtime@e897946

So, from IDE part only deltas should be provided + it will need care about breakpoint location changes (since debugger don't really see line changes in IDE editor). And Hot Reload should work.