[Info-vax] VAX Macro to C conversion

[Bill Gunshannon]

On 6/24/19 7:59 PM, Stephen Hoffman wrote:
> On 2019-06-24 23:43:45 +0000, Andrew Shaw said:
> 
>> ...This is also true and for this I am going to have to do some deeper 
>> analysis of the code (as has been pointed out by others in here) in 
>> order to understand the subtleties of what is going on - hopefully get 
>> an understanding of why it was written in MACRO in the first place. 
>> Our system is a curious mix of languages - MACRO-32, C, FORTRAN and 
>> RATFOR forms the bulk of the system code...
> 
> The use of RATFOR here implies this is an older code-base and/or 
> long-established developers, but that combination of languages is 
> otherwise not particularly unusual.

You thought RATFOR meant an older codebase than FORTRAN?  :-)

> 
> It's fairly common to find that much of the existing Macro32 code can be 
> replaced with rather less C or C++ code, and/or by making calls to 
> now-available system service calls or features.  Or a combination.
> 
> There's a lot of Macro32 around that largely exists for historical 
> reasons and organizational inertia.  "It works" is a strong contributor 
> toward "doing nothing".
> 
> More than a little of the Macro32 was implemented as workarounds for 
> features or APIs that were then-missing, or for APIs that were not 
> easily callable.
> 
> Where folks get in trouble with Macro32 is when Macro32 was used for the 
> last few crumbs of system performance and/or of memory usage.  Or when 
> the developers were too clever. Or a combination.
> 
> Whether separately or as a prolog to the source code conversions, I'd 
> look at adding instrumentation and debugging into the app, and at 
> enabling and cranking up the now-available compiler diagnostics.  If 
> you've VAX C code lurking, switch that all over to C99.
> 
> Starting a source code conversion with latent bugs and/or insufficient 
> test coverage and/or poor telemetry and/or little or no documentation 
> (q.v. doxygen) is not fun.  (n.b. I'm not aware of a doxygen port for 
> OpenVMS, but it does exist for most other platforms.)
> 

Do any of the VMS C Compilers have the equivalent of -S in most
Unix C Compilers?  I would love to see a few simple programs
(starting with "Hello World") written in Macro, converted to C
and then compiled with the option to list the assembler just to
see how they compared.  :-)

bill