[U-Boot-Users] Proposal for a make option to include an additional stand alone program directory

Wolfgang Denk wd at denx.de
Mon Apr 30 21:45:47 CEST 2007

In message <46324857.2020904 at freescale.com> you wrote:
> I really don't want to be arguing the GPL, but I am interested in a technical solution to 
> a problem that is also legally permissible.
> > Merging two binaries into one, so that A can make function calls into
> > B *is* linking if the function of A depends on  the  results  of  the
> > function calls of B.
> How do you determine "depends"?  If B enables the 2nd Ethernet port, but you never 
> actually use it, then A doesn't really depend on B.  Takes these two scenarios:

Depends menas: does not work, or only in a restricted way, without it.

> 1) U-Boot runs the binary application that enables Ethernet 2, but it doesn't load the 
> driver for Ethernet 2.  Therefore, the functioning of U-Boot does not depend on the binary.

Yes, it does, as the function of Ethernet 2 obviously depends on this code.

> > Linux system calls is an explicitely exported interface so it  is  OK
> > to use this from application code.
> So it's okay for a non-GPL binary to call GPL code, but not the other way around?

Please read the specific  licenses.  Any  code  that  only  uses  the
exported  interfaces  can be run under control of the Linux operating
system. But you must take care about which liraries you link against.
They come with their own licenses; for  example,  glibc  comes  under
LGPL which explicitely allows linking against Non-GPL code.

If GPL code can link against non-GPL stuff obviosly  depends  on  the
licensing of that stuff.

> > Please do yourself a favour and re-read the GPL.
> I don't think just reading the GPL is enough to understand it.  Some parts of it are 
> vague, and their interpretations are debatable.

Then please ask a lawyer.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,    CEO: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"Beware of bugs in the above code; I have only proved it correct, not
tried it."                                             - Donald Knuth

More information about the U-Boot mailing list