Sv: g++ and c++17 filesystem

Brian Inglis
Thu Nov 19 15:27:46 GMT 2020

On 2020-11-19 03:03, Kristian Ivarsson via Cygwin wrote:
>>> 18 nov. 2020 kl. 17:26 skrev René Berber via Cygwin <>:
>>> On 11/18/2020 3:00 AM, Kristian Ivarsson via Cygwin wrote:
>>>>>> On 11/17/2020 9:15 AM, Kristian Ivarsson via Cygwin wrote:
>>>>>> The filesystem-library as a part of C++17 seems to have some
>>>>>> defects and flaws in the cygwin-package and pretty much every
>>>>>> lexical- and canonical operation works in mysterious ways (or not
>>>>>> at all)


>> As stated earlier, it seems like using mingw g++/libstdc++ (from the
>> cygwin-package-manager) it seems like it works better, but then you can’t
>> mix with other posix/cygwin mechanism (that uses cygstdc++) without
>> breaking ODR (and probably some memory models etc as well) so maybe
>> someone do have some insightful info about this ? How “special” is
>> cygstdc++ (compared to mingw:s libstdc++) ? Could this be fixable in that
>> library (cygstdc++) ?

> I might be totally wrong, so does anyone have any take on this ?

Cygwin provides cross-tools like djgpp-gcc-core mingw64-i686-gcc-core, 
mingw64-x86_64-gcc-core, cygwin32-gcc-core, cygwin64-gcc-core, and 
djgpp-binutils, mingw64-i686-binutils, mingw64-x86_64-binutils, 
cygwin32-binutils, cygwin64-binutils so anyone has the freedom to choose to 
build DOS, Windows, or Cygwin apps targeting their respective APIs, under 
Cygwin, and also have the freedom to give away or sell those apps as long as 
they respect their licences.

Cygwin's goal is to have everyone and everything believe it is running in a 
POSIX environment and provide interoperability within a Windows environment 
(including Wine) based on POSIX standards, system interfaces, toolchains, 
shells, utilities:

system and network servers and services, plus GUI desktops (GNOME, KDE, LXDE, 
MATE, Plasma, Xfce desktops on X Window System), and apps (task and file 
managers, web browsers, PDF viewers and editors, graphics viewers and editors 
including GIMP). This is all ported and supported by volunteers who believe 
everyone should have a choice, even when for business or family reasons they use 

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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