Subject: Re: libsa/loadfile.c (a.out not working)
To: Michael L. Hitch <>
From: None <>
List: tech-kern
Date: 07/16/2001 14:34:19
> ...
> > 	a_entry of netbsd.aout is 0x2e00. A dump of buff reveals the
> > first 0x2e12 bytes to be zero. MARK_ENTRY points to buff + 0x2e00.
>   Hmm....  How are you defining ALIGNENTRY()?

	As stolen from the news68k port's loadfile_machdep.h :

#define ALIGNENTRY(a)   ((u_long)(a))

> On the amiga, I've got it
> defined as (0) for _STANDALONE (shamelesly copied from the hp300
> loadfile_machdep.h).  I now remember that this was one of the things I had
> to figure out how it worked.

	Aah. Thanks Michael. That is very helpful.

> I still don't completely understand exactly what the ALIGNENTRY()
> is supposed to do

	From its name, I suspected that it aligned the entrypoint
so that it would be suitable as a jump address for the processor,
which might suspend or trap if asked to jump to an odd address.
(i.e. non-word-aligned)

	If it is, in fact, the LOAD ADDRESS of the kernel, then
defining it as 0 makes sense, and would definately fix the problem.

	If it is in fact the latter meaning, it may be nice if
there was a comment beside it's usage (and ideally, its definition
in each port's loadfile_machdep.h). e.g.:

-	minp = maxp = ALIGNENTRY(entry);
+	minp = ALIGNENTRY(entry);	/* Load address */
+	maxp = ~0;

+/* Contrary to its name, this is actually the load address */
-#define ALIGNENTRY(a)	((u_long)(a))
+#define ALIGNENTRY(a)	(0)

	Even better would be to rename it to LOADADDRESS(entry).

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