Re: [PATCH 1/4] u-boot: Update to 2016.09.01 release

["Stefan Müller-Klieser" <s.mueller-klieser@phytec.de>]

On 25.10.2016 21:24, Marek Vasut wrote:
> On 10/25/2016 08:32 PM, Denys Dmytriyenko wrote:
>> On Sat, Oct 22, 2016 at 10:32:12PM +0200, Marek Vasut wrote:
>>> On 10/21/2016 09:47 AM, Burton, Ross wrote:
>>>
>>> Hi!
>>>
>>>> On 20 October 2016 at 14:35, Marek Vasut <marex@denx.de
>>>> <mailto:marex@denx.de>> wrote:
>>>>
>>>>     Upgrade U-Boot to the latest version.
>>>>
>>>>
>>>> As usual, u-boot-mkimage broke again:
>>>
>>> That's weird, I successfully built it for nios2 during my tests.
>>> Can you tell me how I can replicate the issue , so I can test for it to
>>> prevent regression and roll out a patch ?
>>
>> Marek, Ross,
>>
>> Any progress on this? Need any help testing?
>>
> Yeah, how do you replicate this issue ?
> 
Hi!
I am just looking at a similar problem and want to jump into the discussion.
As Ross said, the problem is to not respect host/target -- cc/cflags/ldflags.
So to replicate the issue, you can use a bare minimum build host with no
cross toolchain installed, and I guess all targets will fail to build.
As this has been broken so many times, I want to discuss some possible fixes:
In the top level Makefile we have:
HOSTCC = cc
HOSTCFLAGS = ...
The problem is, you cannot properly override those variables, as they get used
a lot to do different things, e.g. in tools/Makefile we have (for cross tools
target) HOSTCC = $(CC) and for HOSTCFLAGS we have appends for configuration. 
Thats why we have the current workaround with a squashed override. I see many
possible solutions and would like to hear your opinion:
1. Make top level Makefile HOST assignments conditional "?="
   - easy
   - will probably not be accepted upstream
2. add "override" to appends in sublevel Makefiles
   - adds complexity/one level of override hierarchy
3. Don't use appends for those variables (like in the kernel Makefile), overrides
   in the recipe
   - clean
   - quite some rework in uboot
4. Hack around in the recipe with class overrides and exports
   - quickfix, no patch required
   - fails easily in the future

Any thoughts?
Stefan