Compiling Qt application - error: linux/errno.h: No such file

Compiling Qt application - error: linux/errno.h: No such file

[excalamus--- via]

I'm a Python developer familiar with PySide/PyQt teaching myself how to use Qt with C++ and following a tutorial on how to compile a Qt application without QtCreator (https://www.linux.org/threads/c-tutorial-create-qt-applications-without-qtcreator.18409/).  

I've installed what I believe are the necessary Guix packages: gcc (for g++), make, qtbase (for qmake and qtwidgets), and qtdeclarative (because the tutorial uses that later on).  When trying to compile the basic main window I get the following error:

g++ -c -pipe -O2 -Wall -Wextra -D_REENTRANT -fPIC -DQT_DEPRECATED_WARNINGS -DQT_NO_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -I. -I. -I../../.guix-profile/include/qt5 -I../../.guix-profile/include/qt5/QtWidgets -I../../.guix-profile/include/qt5/QtGui -I../../.guix-profile/include/qt5/QtCore -I. -I/gnu/store/m5l6pwzlk3909n9cka9c9qlk7f0lqbig-libdrm-2.4.103/include/libdrm -I../../.guix-profile/lib/qt5/mkspecs/linux-g++ -o main.o main.cpp
In file included from /gnu/store/fa6wj5bxkj5ll1d7292a70knmyl7a0cr-glibc-2.31/include/errno.h:28,
                 from /gnu/store/jc90jrkd40az0zggw84s3ax6m351jlkg-gcc-10.3.0/include/c++/cerrno:42,
                 from /gnu/store/jc90jrkd40az0zggw84s3ax6m351jlkg-gcc-10.3.0/include/c++/ext/string_conversions.h:44,
                 from /gnu/store/jc90jrkd40az0zggw84s3ax6m351jlkg-gcc-10.3.0/include/c++/bits/basic_string.h:6545,
                 from /gnu/store/jc90jrkd40az0zggw84s3ax6m351jlkg-gcc-10.3.0/include/c++/string:55,
                 from ../../.guix-profile/include/qt5/QtCore/qbytearray.h:52,
                 from ../../.guix-profile/include/qt5/QtCore/qstring.h:50,
                 from ../../.guix-profile/include/qt5/QtCore/qobject.h:47,
                 from ../../.guix-profile/include/qt5/QtCore/qabstractanimation.h:43,
                 from ../../.guix-profile/include/qt5/QtCore/QtCore:6,
                 from ../../.guix-profile/include/qt5/QtWidgets/QtWidgetsDepends:3,
                 from ../../.guix-profile/include/qt5/QtWidgets/QtWidgets:3,
                 from main.cpp:2:
/gnu/store/fa6wj5bxkj5ll1d7292a70knmyl7a0cr-glibc-2.31/include/bits/errno.h:26:11: fatal error: linux/errno.h: No such file or directory
   26 | # include <linux/errno.h>
      |           ^~~~~~~~~~~~~~~
compilation terminated.
make: *** [Makefile:1191: main.o] Error 1

If I'm reading the error output correctly, the error occurs when trying to compile the main.cpp object file which uses includes the QtWidgets module.  The error is in that portion of the source, so I don't think there's anything I could comment out from the makefile.

Browsing the documentation for glibc, it looks like linux/errno.h is a glibc extension.  Is that not included in the Guix glibc package?  I don't see another Guix package for glibc extensions.

Re: Compiling Qt application - error: linux/errno.h: No such file

[Tobias Geerinckx-Rice]

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Ave,

excalamus--- via 写道：
> /gnu/store/fa6wj5bxkj5ll1d7292a70knmyl7a0cr-glibc-2.31/include/bits/errno.h:26:11: 
> fatal error: linux/errno.h: No such file or directory
>    26 | # include <linux/errno.h>
>       |           ^~~~~~~~~~~~~~~
> compilation terminated.
> make: *** [Makefile:1191: main.o] Error 1

Does including linux-libre-headers in the environment help?

Kind regards,

T G-R

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Re: Compiling Qt application - error: linux/errno.h: No such file

[excalamus--- via]

> Does including linux-libre-headers in the environment help?
>
It doesn't appear so. I had installed the glibc package previously (although I assumed it was part of the GCC deps). Trying to install the headers complained about conflicts with the glibc package. Uninstalled glibc and installed the headers. Same error.
 
I'm running Guix SD.  That should automatically set environment variables after install, correct? (not sure what to export anyways)

Re: Compiling Qt application - error: linux/errno.h: No such file

[excalamus--- via]

It works now!

In all fairness, it didn't work immediately. Because life is so busy, I had to shut down and on restart (however long after my last message) ran guix pull followed by guix package -u. Running make then compiled without issue. I see that sweet, sweet main window! 
Thank you so much for your help! I've been developing Qt for Python for years and am so excited to work with C++. 8D