[m-dev.] for review: line numbers for output streams

[Fergus Henderson]

Thomas Charles CONWAY, you wrote:
> 
> What is the status (I can't remember) of #line directives?
> Zoltan had something almost going a while back...

There's two aspects to that:

(a) `#<line number>' directives in Mercury

	These are implemented, documented, and work fine.
	The only thing is that Zoltan suggested that the
	syntax be changed to `#line <line number>'.
	This has not been done.

(b) `#line' directives in the generated C code.

	There is some code in there that puts #line directives
	before outputing code from `pragma c_code' declarations,
	but
		(i) it puts the #line directives in the wrong place

		(ii) it doesn't output a #line directive at the end,
		so that any errors in the automatically generated C code
		get the right location (this wasn't done because it
		needs the new predicates I just added)

		(iii) Zoltan claimed that when they were enabled,
		his compiler didn't bootstrap.  Hence, they are
		commented out.  However, I think it was probably cosmic
		rays, and when we have fixed (i) and (ii) we should
		uncomment it.

-- 
Fergus Henderson <fjh at cs.mu.oz.au>   |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>   |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3         |     -- the last words of T. S. Garp.