[PATCH] D28791: [compiler-rt][crt] Simple crtbegin and crtend implementation

[Chandler Carruth via Phabricator via llvm-commits]

chandlerc added inline comments.


================
Comment at: lib/crt/crtbegin.c:5-6
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
----------------
emaste wrote:
> beanz wrote:
> > phosek wrote:
> > > emaste wrote:
> > > > As this file would be linked into all executables produced by the toolchain, should it be an exception to the standard LLVM MIT/UIUC license - i.e., 0-clause BSD or CC0?
> > > > 
> > > > https://tldrlegal.com/license/bsd-0-clause-license
> > > > https://creativecommons.org/share-your-work/public-domain/cc0/
> > > I'd be fine with that.
> > I've asked @chandlerc to chime in either himself, or someone from the foundation. My understanding of the way we handle licensing in LLVM is that only the runtime libraries are dual licensed UIUC & MIT. The reason being that the MIT license doesn't have the same attribution requirements as UIUC. LLVM, Clang, LLDB, LLD, etc. are all UIUC licensed only.
> > 
> > Since all of compiler-rt is under the UIUC/MIT dual license, I would be very concerned if this file needed different licensing since lib/builtins all get embedded in binaries in the same way, and are under that same license configuration.
> Thanks, and fair enough.
> 
> > The reason being that the MIT license doesn't have the same attribution requirements
> 
> I agree with you there's no need for this file to be licensed differently from the rest of the runtime components, and agree with the goal of avoiding attribution requirements on runtime components.
> 
> That said, a quick search turns up lots of opinions on MIT attribution and binary distribution from non-lawyers (and I am, of course, not a lawyer).
> 
> So, I think there's nothing to do for this file in isolation, but we should ensure the runtime components have the expected requirement (i.e., none) for binaries.
> 
> (I seem to recall being involved in a previous discussion of this with @chandlerc, but now cannot find any evidence of that discussion.)
We should not add more license diversity here. The current license structure of compiler-rt was an attempt to provide a workable license for runtime libraries in LLVM and they should continue to be used for this component of the runtime libraries.

There are many problems with the license structure we ended up with (see Chris's original emails), and indeed we are working on relicensing all of LLVM to address these concerns. We have worked *very* hard with lawyers to make sure the new license is an excellent choice for runtimes. I would encourage any further efforts to go into the new license, and I think being consistent with the rest of compiler-rt is fine in the interim.


Repository:
  rL LLVM

https://reviews.llvm.org/D28791