Re: Request to rename version.h

[Mojca M. <moj...@gm...>]

Hi,

I just got a confirmation from one of the Apple developers working on
the compiler that
    "This is (unfortunately) correct behavior from the perspective of
the toolchain"

On Tue, 5 Nov 2019 at 22:43, Hans-Bernhard Bröker wrote:
> Am 05.11.2019 um 20:03 schrieb Achim Gratz:
> > The common file systems on Windows are case-preserving and
> > case-insensitive, but not case-ignoring.  Would that explain the
> > difference?
>
> I very much doubt it.
>
> 1) And as far as I'm aware, MacOS has the same features, and does
> exhibit the problem.
>
> 2) Case-preservance only makes a difference when asking a file for its
> name or listing the files in a directory, but not when searching for a
> file by name, along a path list.  Rather that's where the insensitivity
> hits.  A path search mechanism would have to go out of its way to read
> back the actual file name of any file it found, to see if the case
> matches, too.
>
> On inspection I did not find any mention of <version> in the dependency
> information collected by my local compilations, though.  So possibly my
> local, MinGW and Cygwin versions of the tools and libraries in question
> (wxWindows, stdc++, ...) are not quite new enough to trigger the problem.

I tried to reproduce the problem on msys2 (MinGW64) on Windows. I
could easily reproduce the problem with:

$ cat VERSION
1.0

$ cat test.cpp
#include <version>
int main() { return 0 }

$ clang++ test.cpp -I.

but on macOS I also get the problem with as trivial minimal example as

$ cat test.cpp
#include <memory>
int main() { return 0 }

The main difference is that the included file <memory> on MSYS2
apparently comes from FSF (the header mentions the licence GPL v3),
it's thus a completely different header and as a consequence one
doesn't immediately see the same behaviour. But if I edit the "memory"
file and only add
    #include <version>
there, then the local VERSION file is picked up, so it's basically the
same behaviour as on macOS.

$ clang++ test.cpp -I.
In file included from test.cpp:1:
In file included from
C:\Programs\MSYS\msys64\mingw64\include\c++\9.2.0\memory:3:
.\version:1:1: error: expected unqualified-id
1.0
^
1 error generated.

So all in all, I would be really grateful if VERSION file could be renamed.

(According to our limited opt-in installation statistics, gnuplot seem
to be the 21st most popular explicitly installed package, and having
it broken is not really the best option. We monkey-patched it for now,
but it would be great to have a proper solution in place.)

Mojca