[CMake] globs case sensitivity depends on platform

[🐋 Jan Hegewald]

Hi Andreas,

thanks for bearing with me (-:

> On 28.01.2016, at 20:28, Andreas Pakulat <apaku at gmx.de> wrote:
> 
> Hi Jan,
> 
> On Thu, Jan 28, 2016 at 4:52 PM, 🐋 Jan Hegewald <jan.hegewald at awi.de> wrote:
> Hi Andreas,
> 
> > On 28.01.2016, at 16:43, Andreas Pakulat <apaku at gmx.de> wrote:
> >
> > Hi Jan,
> >
> > On Thu, Jan 28, 2016 at 2:35 PM, 🐋 Jan Hegewald <jan.hegewald at awi.de> wrote:
> > Hi Nils,
> >
> > > On 28.01.2016, at 13:39, Nils Gladitz <nilsgladitz at gmail.com> wrote:
> > >
> > > You might already be aware but CMake discourages using GLOB for source files
> >
> > yes, I read the docs before posting (:
> > Avoiding glob would be a workaround to my problem. But anyway I think that glob is broken if it produces different results on different platforms.
> >
> > I can't find any docs on cmake.org about what a globbing-expression is exactly, but the docs for file(glob) at least don't say anything about this function producing the same results on different platforms. In fact I'd be surprised if the behavior of the file(glob) function is different than using the same wildcards with ls/dir on a terminal.
> 
> the cmake glob is different from the results of a terminal ls
> 
> On the Mac apparently (based on your first mail)

Yes, on the Mac. ls behaves the same on both platforms.

> 
> > The only bug that I can see from your description is that the behavior is inconsistent with different types of FS on OSX, that is definetly not matching above mentioned expectation.
> 
> Maybe I was unclear about this, but cmake glob ignores the case regardless of the FS being case sensitive or not.
> 
> Now that contradicts your initial mail, you said there that on OSX you get F* and f* files for a case-insensitive filesystem, but on Linux you get only F*. But you also said that a case-sensitive filesystem on OSX still gives you F* and f* files, which in my eyes is a bug in the implementation.

Yes. On the Mac I get the same unexpected results for case sensitive and case insensitive FS (i.e. glob returns files with different cases).

> 
> I also just checked the CMake sources quickly and it seems that the glob-support is completely 'inhouse', meaning it does not call out to platform-specific functions (I guess that would explain the discrepancy on OSX).
> 
> So I guess asking for the same behavior across platforms is just as reasonable (given the logics are fully under CMake's control) as asking for it to reflect what a ls/dir would do on the corresponding platform.
> 
> I think a bugreport is the correct next step, even if it merely leads to a clarification of the behavior in the documentation.
> 
> Andreas

OK, I did that: https://public.kitware.com/Bug/view.php?id=15941

FYI, regarding the specification of glob patterns there is https://public.kitware.com/Bug/view.php?id=8814

Best,
Jan