Re: gpl, gdb and wigglers.dll

[Stan Shebs <shebs@apple.com>]

Andrew Cagney wrote:
> 
> [...] should GDB
> even include the source to code that allows it to use proprietary debug
> interfaces?  I'm guessing, but I suspect that the current pratice has
> been that such code should be included as it makes GDB accessible to a
> wider set of users.  At the same time, however, it also precluding the
> possibility of a dll vendor directly benefiting by distributing a GDB
> binary.

I don't believe this practice violates the letter of the GPL, but
it is in a gray area.  The GPL says source code need not "include
anything that is normally distributed with [...] the operating
system".  The wiggler dll is basically a driver for an addon piece
of hardware, so one could argue that it is a normal component of the
operating system for a PC+wiggler combination.  In that respect it
would be no different from having, say, an XFree86 that includes a
special hack to use a Windows-binary-only 3D card driver, even when
running on GNU/Linux.

However, in retrospect, I made a mistake in deciding to include
ser-ocd.c.  The problem is that with an unspecified interface
between PC and wiggler, and with the wiggler dll only available in
binary form for certain platforms (correct me if I'm wrong here),
you have the situation that the GPL was supposed to prevent, namely
that you can't fix a problem in the driver, use it with a different
operating system, etc.  For instance, if I get a Mac with a parallel
port, I can't use the wiggler I already bought, no matter whether I run
LinuxPPC or OS X.  Even a minor Linux or Windows upgrade could render
my wiggler useless.

So as a matter of principle, it would be better to remove ser-ocd.c
from the sources and explain why.  Perhaps the official deprecation
will encourage someone to work up some free source that will work
with a wiggler, much as was done for m68k bdm years ago (though never
incorporated into GDB, sigh).

Stan