t-frame-pointer -fexceptions -Wall -Wextra -pedantic -DNDEBUG -Wl,-z,relro -Wl,--as-needed  -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -Wl,--build-id=sha1 -specs=/usr/lib/rpm/redhat/redhat-package-notes CMakeFiles/simpleplot.dir/simpleplot_autogen/mocs_compilation.cpp.o CMakeFiles/simpleplot.dir/simpleplot.cpp.o -o simpleplot  -Wl,-rpath,/builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/redhat-linux-build ../../libqwtplot3d-qt6.so.0.3.0 -lgl2ps /usr/lib64/libGLU.so /usr/lib64/libQt6OpenGLWidgets.so.6.6.0 /usr/lib64/libQt6OpenGL.so.6.6.0 /usr/lib64/libQt6Widgets.so.6.6.0 /usr/lib64/libQt6Gui.so.6.6.0 /usr/lib64/libQt6Core.so.6.6.0 /usr/lib64/libGLX.so /usr/lib64/libOpenGL.so /usr/lib64/libgl2ps.so 
gmake[2]: Leaving directory '/builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/redhat-linux-build'
[ 92%] Built target simpleplot
[ 94%] Building CXX object examples/mesh2/CMakeFiles/mesh2.dir/designerworkaround.cpp.o
cd /builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/redhat-linux-build/examples/mesh2 && /usr/bin/g++ -DQT_CORE_LIB -DQT_GUI_LIB -DQT_NO_DEBUG -DQT_OPENGLWIDGETS_LIB -DQT_OPENGL_LIB -DQT_WIDGETS_LIB -I/builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/redhat-linux-build/examples/mesh2/mesh2_autogen/include -I/builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/include -I/builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/redhat-linux-build -isystem /usr/include/qt6/QtCore -isystem /usr/include/qt6 -isystem /usr/lib64/qt6/mkspecs/linux-g++ -isystem /usr/include/qt6/QtGui -isystem /usr/include/qt6/QtOpenGLWidgets -isystem /usr/include/qt6/QtOpenGL -isystem /usr/include/qt6/QtWidgets -O2  -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -fasynchronous-unwind-tables -fno-omit-frame-pointer -fexceptions -Wall -Wextra -pedantic -DNDEBUG -std=c++17 -MD -MT examples/mesh2/CMakeFiles/mesh2.dir/designerworkaround.cpp.o -MF CMakeFiles/mesh2.dir/designerworkaround.cpp.o.d -o CMakeFiles/mesh2.dir/designerworkaround.cpp.o -c /builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/examples/mesh2/designerworkaround.cpp
The bug is not reproducible, so it is likely a hardware or OS problem.
gmake[2]: *** [examples/mesh2/CMakeFiles/mesh2.dir/build.make:112: examples/mesh2/CMakeFiles/mesh2.dir/mesh2_autogen/mocs_compilation.cpp.o] Error 1
gmake[2]: *** Waiting for unfinished jobs....
gmake[2]: Leaving directory '/builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/redhat-linux-build'
gmake[1]: Leaving directory '/builddir/build/BUILD/qwtplot3d-b2655743d30ed3185f3c0e2626b33a1d29655216/qwtplot3d-qt6/redhat-linux-build'
gmake[1]: *** [CMakeFiles/Makefile2:408: examples/mesh2/CMakeFiles/mesh2.dir/all] Error 2
gmake: *** [Makefile:139: all] Error 2
error: Bad exit status from /var/tmp/rpm-tmp.0tNnzO (%build)
    %patchN is deprecated (2 usages found), use %patch N (or %patch -P N)
    Bad exit status from /var/tmp/rpm-tmp.0tNnzO (%build)
RPM build warnings:
RPM build errors:
Child return code was: 1
EXCEPTION: [Error()]
Traceback (most recent call last):
  File "/usr/lib/python3.9/site-packages/mockbuild/trace_decorator.py", line 93, in trace
    result = func(*args, **kw)
  File "/usr/lib/python3.9/site-packages/mockbuild/util.py", line 600, in do_with_status
    raise exception.Error("Command failed: \n # %s\n%s" % (command, output), child.returncode)
mockbuild.exception.Error: Command failed: 
 # bash --login -c /usr/bin/rpmbuild -bb --target riscv64 --nodeps /builddir/build/SPECS/qwtplot3d.spec