[Info-vax] LLVM, volatile and async VMS I/O and system calls

[Stephen Hoffman]

On 2021-10-02 23:38:12 +0000, chris said:

> No, really trolling, just saw your original post as arm waving in 
> respect of some mysterious process, as yet undiscovered, that could 
> cause havoc to vms builds. As I said upthread, vms has been rewritten 
> twice already, so sure such issues would have been noticed and dealt 
> with.

OpenVMS has been ported, yes. OpenVMS has not been rewritten twice. 
Each port further isolates the platform-independent from the 
platform-specific too, while the vast majority of the existing source 
code is unchanged.

Previous ports have shown weird bugs, those latent in the existing 
codebase that was ported, those bugs introduced by the platform tools, 
and those exposed by (for instance) updated processors of the same 
architecture. q.v. SRM_CHECK.

Some enhancements and optimizations have exposed latent bugs in the 
platform and in apps, too. The async I/O completion work from (as it 
was then known) VAX/VMS 5.0 field test exposed myriad latent errors, 
and was backed out for the V5.0 release.

Hyrum's Law: With a sufficient number of users of an API, it does not 
matter what you promise in the contract: all observable behaviors of 
your system will be depended on by somebody."

And some of us would be interested in some Arm waving too, but for now 
it's all x86-64 waving.



-- 
Pure Personal Opinion | HoffmanLabs LLC