[Info-vax] x86-64 data aligment / faulting

[John Reagan]

On Wednesday, March 16, 2022 at 8:36:09 AM UTC-4, John Dallman wrote:
> In article <4ff9c36f-5aef-4753... at googlegroups.com>,
> xyzz... at gmail.com (John Reagan) wrote: 
> 
> > On x86, at this point, we don't even turn on the trapping. I'm 
> > sure there are hardware performance registers that count them 
> > globally but OpenVMS doesn't ask about that.
> Presumably the compilers - both GEM-based and LLVM - will use natural 
> alignment by default? 
> 
> John
Our Alpha and Itanium frontends are already natural alignment by default (COBOL
is the exception).  Nothing changed for x86. 

You can use various pragmas like nomember_alignment, pack(0), etc. to place structure
fields in whatever offset you prefer.