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- Hacker News
- I like this emulation feature. A frontend capable of mimicking MSVC or GCC behavior seems very useful for porting code or developing tools that need to exactly replicate the operation of another compiler.
- One interesting thing about the EDG front end is that it can emulate all the others (and in various versions of the others) and what they support, and the errors they might detect.
It isn't perfect, but it is awfully good.
Another interesting thing is that in 1999ish, when SGI open-sourced the Irix compiler (known as sgicc) into open-64, the it used a terribly hacked version of gcc as a front end to generate its internal intermediate representation.
This was because sgicc, even back then, used EDG as a front end, and EDG wasn't open and couldn't be opened up at the time.
The combination worked OK, but was pretty hacky, and I wonder if open64 would have gotten more traction than it did if it had been able to use EDG, or perhaps some other front end actually designed as a front end instead of the hacky thing.
by compiler-guy - If I remember correctly, EDG was the only C++ implementation that actually attempted to implement the export keyword for templates in old C++. It was this implementation experience that informed the deprecation of export. EDG is a major influence in the development of C++.by kccqzy
- Announcement: https://edgcpp.org/#transition
The source code itself: https://github.com/edgcpp/compiler
Documentation: https://edgcpp.org/doc/
And for those curious the license SPDX is: Apache-2.0 WITH LLVM-exception
i.e.
- It's got history! That's really unusual for moves to open-source; the dates on the earliest commits are in 1990 and they do go forward in time so that's really unusual to have that much history. I bet there's some fun stuff in there.by trebligdivad
- Wow. This is big news for C++.
For background -- and I am not an expert here -- their C++ frontend is widely known. I first heard of it because Visual C++'s Intellisense uses it, which was notable because VC does not use the msvc frontend for its own completion. I understand it's been either used or evaluated for other frontends in the past too. I worked as PM for one C++ product, and was fortunate to be able to learn a lot from our engineers; we didn't use it, but they thought highly of EDG.
It has a very strong reputation for being correct. And as such, I think open sourcing it will be a very beneficial thing for the C++ community.
by vintagedave - I wonder if the source-to-source compilation could be used to transpile C++ code/libraries to other languages - e.g. could this be used (with appropriate modifications of course) to compile FLTK into Free Pascal code and used directly by Lazarus as a backend for LCL? Trying to use C++ libraries from non-C++ is always a PITA, especially if you want to avoid dynamic linking.
Also, since i mentioned Lazarus, if it can compile itself to Free Pascal, i wonder if it'd be useful for adding C++ support to Lazarus itself so that Free Pascal and C/C++ can be mixed in a project to make self-contained executables for desktop applications. It'd most likely need much more work than that just the compilation to make it a first class citizen like Free Pascal itself is for Lazarus/LCL (e.g. things like the object inspector and code tools being able to understand C++ well enough so that refactoring and stuff like doubleclicking on a button in a form automatically declaring and defining the handler and moving the editor cursor to the newly defined handler's code body), but maybe it could be used as a starting point.
- What's not mentioned in the announcement (at least based on a quick skim) is that EDG the company is winding down, which is likely the reason why they're open sourcing the front end.
https://en.wikipedia.org/wiki/Edison_Design_Group ref 9: https://herbsutter.com/2025/11/10/trip-report-november-2025-...
by jabl