[FFmpeg-devel] [PATCH] build: fix make checkheaders in out-of-tree builds

[Hendrik Leppkes]

On Sun, Jan 24, 2016 at 8:51 PM, Andreas Cadhalpun
<andreas.cadhalpun at googlemail.com> wrote:
> On 24.01.2016 20:40, Hendrik Leppkes wrote:
>> On Sun, Jan 24, 2016 at 7:27 PM, Andreas Cadhalpun
>> <andreas.cadhalpun at googlemail.com> wrote:
>>> On 24.01.2016 17:14, Henrik Gramner wrote:
>>> I have a hard time believing that there are environments, where one
>>> can't use absolute paths...
>>
>> Its about the combination of msys and its automatic path translation
>> and the special option syntax msvc uses which msys doesn't recognize,
>> otherwise it would be fine.
>> But alas it is how it is, and we have to deal with what we have.
>
> :-/
>
>>> OK, let's try this.
>>> Attached is a patch calculating dst_path as relative path.
>>> That should hopefully work everywhere. Please test it.
>>>
>>
>> Unfortunately that doesn't work when there is no common path, ie.
>> sources on another drive (say D:) as my build directory (say C:)
>
> Don't do that then?

Thats not an answer.

>
>> The script produces a long chain of "../.." then of course, which
>> would work on a unix-like filesystem, but the only way to switch
>> drives in windows-path is using absolute paths.
>
> Why does it not work with relative paths?
> That looks like (another) bug in that environment.
>

Its just how it works. Relative paths can't switch drive in windows
path, no matter how many ..'s you chain.
Once you hit the root of a drive, .. just redirects to itself, just
like a unix / would, except that you get one per drive instead of a
global one.

- Hendrik