Dear "Neugebauer, Manfred",
In message 1B9C02DB7C62FE44B8FAC992AAC75E8E16472581@DEFTHW99E85MSX.ww902.siemens.net you wrote:
I have a question concerning standalone programs based on u-boot and GPL, since I'm not really sure whether the way how the u-boot source files are set up allows GPL free standalone programs.
This is the intention; if the current code or documentation should conflict with this intention, it should be fixed.
However, when looking at the GPL details, I'm not sure whether this really works with the current u-boot sources (from a legal point of view):
(a) the source code of the hello_world example for a standalone application has a GPL header. If you are legally strict, this can mean every standalone application is a derived work from this example and therefore restricted to GPL.
I disagree.
You should be able to write standalone aplications without ever looking at the hello_world.c file.
(b) When you want to write a standalone application you need - as a minimum - to include "exports.h" (for the interface definitions), which requires "common.h" as additional header file. Both files are not included in the COPYING information which allows the use outside of GPL. The header file "common.h" (and other header files, which are included within common.h) even have a GPL header.
"exports.h" should be added to the "allowed" file list; there should be no need to include "common.h". Eventually this needs fixing. Patches are welcome.
(c) you need to link your standalone application against stub.o (or the corresponding library). I did not find any statement (e.g., within stub.c), that this part is GPL-free (e.g., similar to LGPL).
"examples/standalone/stubs.c" should be added to the "allowed" file list (the ppc_*jmp.S files are LGPLed).
So, from my point of view (although I'm not a lawyer), there are some doubts about a GPL free standalone application based on the actual
There should be no doubts - the intention is clear, the current state may need improvement. Help (read: patches) welcome.
u-boot sources. I believe there should be some enhancements to clarify this subject:
(1) GPL free standalone examples (2) a really GPL free exports.h (similar to include/image.h) (3) some explanations that the use of the source file "examples/standalone/stub.c" is not GPL restricted.
Agreed.
I know that this is a very strict view to this subject (but that is the way legal people look at it). I'm interested in a feedback from others who already were involved with this issue.
There is two ways to deal with licenses: either ignore them completely, or be really strict about them. I think we all agree that we cannot ignore them, so we have little choice but trying to improve what we have.
Best regards,
Wolfgang Denk