Re: ISO: The Eiffel OO programming language and IDE, on VMS

On 3/26/2025 2:57 PM, Simon Clubley wrote:

On 2025-03-26, Arne Vajhøj <arne@vajhoej.dk> wrote:

On 3/26/2025 1:09 AM, David Meyer wrote:

Is there anything in the VSI licensing that would prevent a community of
VMS and Rust (for example) fans from developing a VMS port of a Rust
compiler and releasing the compiler as open source?

>
No.
>
VMS users can write or port all the compilers they want to. And
they have done so in the past: old versions of GCC C and C++ ran on
VMS VAX and VMS Alpha, old versions of Gnat Ada ran on VMS Alpha
and VMS Itanium.
>
The reason it is not happening is not license restrictions, but
lack of interest (willing to do work type of interest - not
it would be nice if somebody else did the work interest) in
the VMS community.
>

 In the case of rust there are major technical reasons. See below.
 

The specific discussion was about the LLVM compiler backend,
that VSI use for their compilers. If VSI made that available
(it is open source) then it would be easier for people to
write or port new compilers using LLVM as backend.

 Would any rust toolkit version even build with the version of LLVM
that VSI use ?
 This posting claims LLVM version 17 is a minimum for the current version
of rust:
 https://users.rust-lang.org/t/does-anyone-know-the-lowest-version-of-llvm-that-rust18-can-use/120096
 How far back would you have to go before you find a rust version that
would build with the LLVM version VSI have currently ported ?

I believe VMS use LLVM 3.4.2 from 2014.
So an early Rust version may work with it, but not a
relevant version of Rust.
VSI release of VMS changes to current LLVM will not help
a community VMS Rust project.
VSI LLVM upgrade and release of VMS changes would help.
Else the community could do a port of recent version. Not
likely, but theoretical possible (35 years ago GCC was
ported to VMS VAX and 25 years ago GCC was ported to
VMS Alpha).
Arne