Subject: Re: sun-lamp CVS commits
To: The Source Master <srcmastr@NetBSD.ORG>
From: J.T. Conklin <jconklin@netcom.com>
List: source-changes
Date: 12/11/1994 15:56:41
> Modified Files:
> 	Makefile.inc devname.c err.c getbsize.c getnetgrent.c 
> 	initgroups.c 
> Added Files:
> 	__err.c 
> Log Message:
> - Changed all internal libc references of {v,}err{x,} and {v,}warn{x,} to
>   __{v,}err{x,} and __{v,}warn{x,}
> - moved err.c to __err.c and added err.c which contains weak references for
>   the above functions.
> - Reordered the functions in __err.c to avoid redeclarations and changed
>   the varargs declarations to conform with the K&R style.

These changes are not consistant with my not-yet-published strategy on
how we should handle weak/indirect references.  Of course Christos had 
no way to know that, and the errors needed to be fixed so people could
compile the source.

Based on responses received from my recent posting on tech-userlevel,
these are my recommendations on how we should procede:

	1. NetBSD needs real weak references.  This can be accomplished 
	   by merging the current gas/ld a.out weak reference support
	   into NetBSD, or by merging NetBSD's shared library support
	   into gas/ld.  Both strategies have their own advantages
	   and disadvantages.  I'll address them in a future message
	   because I don't want to cloud the immediate issues.

As the bug that this fix demonstrates, we sometimes will not be in a
position to wait for the real weak references.  To work around this
deficiency, we will use the indirect reference support in NetBSD's
assembler and linker.

	2. All functions will remain in their original containing files
	   (files will not be renamed).

	3. All functions that need to be namespace protected will be 
	   renamed to have a single leading underscore.  There are some
	   functions in the NetBSD C library that still have double
	   underscores.  This was caused by me missreading a section
	   of the C standard, and will be fixed soon.

	   Advantages of a single underscore include short
	   identifiers, and consistancy with the Svr4 ABI (programs like 
	   autoconf search for the single underscore forms of identifiers).

	4. Ideally, object files containing directives to will be generated 
	   programmatically from make files. Until that mechanism is
	   in place, the mappings will be stored in "stub" files named
	   by catenating a single underscore and the function name.

When we get real weak symbols, we will:

	5. Remove any remaining "stub" files and makefile junk, and add
	   weak symbol entries directly to the function's source files
	   as follows:

		#pragma weak foo=_foo

	--jtc