[Info-vax] RMS and SSIO (again)

[John Reagan]

On Wednesday, January 12, 2022 at 2:23:07 PM UTC-5, Simon Clubley wrote:
> On 2022-01-11, John Dallman <j... at cix.co.uk> wrote:
> > In article <srkj4r$m7g$2... at dont-email.me>, 
> > clubley at remove_me.eisner.decus.org-Earth.UFP (Simon Clubley) wrote: 
> > 
> >> However, at that time, John was planning to add this to the LLVM 
> >> based compilers at some point. I don't know the current status of 
> >> that. 
> > 
> > Most of that will come free with the LLVM compilers. The thing that will 
> > probably be different is the error generation when checks are failed. On 
> > OSes where I've used stack buffer overflow protection, failing a check 
> > generally terminates the process. 
> >
> In addition to the usual suspects, John was also talking at the time 
> about seeing if this could be added into the Macro-32 and BLISS compilers 
> due to the amount of code in VMS which is written in those languages.
> >> Do any of the DEC compilers generate code that executes on the stack 
> >> at runtime ? 
> > 
> > I doubt it. 
> >
> Do any of the DEC compilers generate trampoline functions on the stack ?

No code on the stack.  The x86 stack is marked no-execute.  The trampolines
are created by the linker with some image activator fix ups and then marked nowrite
before any code is executed.

For stack-smashing, it is still on the list. As we get native compilers in place, we'll
revisit it.  Macro might be a touch harder with routines that branch between each
other.