qwt qwt/6.2.0: Build error's when overriding Qt version

[ashley-b]

Description

When installing qwt/6.2.0 with qt/6.3.0 I get a build error from gcc: Qt requires a C++17 compiler

Package and Environment Details

• Package Name/Version: qwt/6.2.0
• Operating System+version: Linux Ubuntu 18.04
• Compiler+version: GCC 8
• Docker image: conanio/gcc8
• Conan version: Conan 1.59.0
• Python version: Python 3.7.13

Conan profile

Configuration for profile default:

[settings]
os=Linux
os_build=Linux
arch=x86_64
arch_build=x86_64
compiler=gcc
compiler.version=8
compiler.libcxx=libstdc++11
build_type=Release
[options]
[conf]
[build_requires]
[env]

Steps to reproduce

Following command run from inside conanio/gcc8 docker container

conan install  qwt/6.2.0@ --require-override qt/6.3.0 -pr:h default -pr:b default -u -b missing -c tools.system.package_manager:mode=install -c tools.system.package_manager:sudo=True

Logs

Click to expand log

[ 14%] Building CXX object src/CMakeFiles/qwt_objects.dir/qwt_magnifier.cpp.o
In file included from /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/src/src/qwt_global.h:13,
                 from /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/src/src/qwt_graphic.h:13,
                 from /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/src/src/qwt_graphic.cpp:10:
/home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtCore/qglobal.h:125:6: error: #error "Qt requires a C++17 compiler"
 #    error "Qt requires a C++17 compiler"
      ^~~~~

[EstebanDugueperoux2]

Hi @ashley-b,

according to https://doc.qt.io/qt-6/supported-platforms.html minimal gcc requirement is GCC 9.
Perhaps qt conan recipe could be improved about that.

[ashley-b]

Hi @EstebanDugueperoux2,

qt/6.3.0 did build successfully in conanio/gcc8:latest container, but qwt/6.2.0 failed.
With VERBOSE on the compiler arguments look like this. C++ version is forced to c++11

[ 14%] Building CXX object src/CMakeFiles/qwt_objects.dir/qwt_magnifier.cpp.o
cd /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/build/Release/src && /usr/bin/g++ -DFFI_BUILDING -DLIBXML_STATIC -DPCRE2_STATIC -DQT_CONCURRENT_LIB -DQT_CORE_LIB -DQT_GUI_LIB -DQT_NO_KEYWORDS -DQT_O
PENGLWIDGETS_LIB -DQT_OPENGL_LIB -DQT_PRINTSUPPORT_LIB -DQT_STRICT_ITERATORS -DQT_WIDGETS_LIB -DQWT_MOC_INCLUDE -DQWT_NO_SVG -DU_STATIC_IMPLEMENTATION -DXML_STATIC -I/home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcda
befb23b64944/build/Release/src/qwt_objects_autogen/include -isystem /home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include -isystem /home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a001
0b85f7826c4d07ac12/include/QtCore -isystem /home/conan/.conan/data/zlib/1.2.12/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/include -isystem /home/conan/.conan/data/pcre2/10.37/_/_/package/63e2e082db68514d73a3597341e8a175e002e762/
include -isystem /home/conan/.conan/data/bzip2/1.0.8/_/_/package/a5875aed3fc7ae8dd0488f7e5e99acbc480d721d/include -isystem /home/conan/.conan/data/double-conversion/3.2.0/_/_/package/56e0cf6d16ee57367a0661ab743f4e43b29223f8/include -isyst
em /home/conan/.conan/data/icu/71.1/_/_/package/e9d2554556d77c2b930cb43fee1cf1b2036c86a7/include -isystem /home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtConcurrent -isystem /home/conan/.con
an/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtPrintSupport -isystem /home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtGui -isystem /home/conan/.conan/data/fre
etype/2.12.1/_/_/package/5cb6fe105f36831a2c2b03ab53c73974c359b192/include -isystem /home/conan/.conan/data/freetype/2.12.1/_/_/package/5cb6fe105f36831a2c2b03ab53c73974c359b192/include/freetype2 -isystem /home/conan/.conan/data/libpng/1.6.
37/_/_/package/c5f06ea0d3a7d6f35f03d832e3609fcc34e36a44/include -isystem /home/conan/.conan/data/brotli/1.0.9/_/_/package/224dcd91ed677bf7e341484d95860c4bc8fdde41/include -isystem /home/conan/.conan/data/brotli/1.0.9/_/_/package/224dcd91e
d677bf7e341484d95860c4bc8fdde41/include/brotli -isystem /home/conan/.conan/data/fontconfig/2.13.93/_/_/package/d8858e187cb415894861d32e891e69d5d34c2e1a/include -isystem /home/conan/.conan/data/expat/2.5.0/_/_/package/9a29d10b97b42a53958ce
2a89aa2fe8027567806/include -isystem /home/conan/.conan/data/libuuid/1.0.3/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/include -isystem /home/conan/.conan/data/libuuid/1.0.3/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/in
clude/uuid -isystem /usr/include/uuid -isystem /home/conan/.conan/data/wayland/1.21.0/_/_/package/e03b7a95afb3f8592db7fbbfc064dda3c6b2962a/include -isystem /home/conan/.conan/data/libffi/3.4.3/_/_/package/1d877a3df840030e6a8abb74c5ffb9088
d08b47a/include -isystem /home/conan/.conan/data/xkbcommon/1.4.1/_/_/package/32f30edd12cd947a8e026711c233844c6677ddbe/include -isystem /home/conan/.conan/data/libxml2/2.10.3/_/_/package/ef73374486ad1894a99815dc78ddec5b517ae320/include -is
ystem /home/conan/.conan/data/libxml2/2.10.3/_/_/package/ef73374486ad1894a99815dc78ddec5b517ae320/include/libxml2 -isystem /home/conan/.conan/data/libiconv/1.17/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/include -isystem /usr/in
clude/libdrm -isystem /home/conan/.conan/data/harfbuzz/4.4.1/_/_/package/d52cbe692d0e339b67aa3ab317dd44fe82e14052/include -isystem /home/conan/.conan/data/harfbuzz/4.4.1/_/_/package/d52cbe692d0e339b67aa3ab317dd44fe82e14052/include/harfbuzz -isystem /home/conan/.conan/data/glib/2.75.2/_/_/package/02ae235820b1cc0e761686ccf0ced4cb8b458c83/include/gio-unix-2.0 -isystem /home/conan/.conan/data/glib/2.75.2/_/_/package/02ae235820b1cc0e761686ccf0ced4cb8b458c83/include -isystem /home/conan/.conan/data/glib/2.75.2/_/_/package/02ae235820b1cc0e761686ccf0ced4cb8b458c83/include/glib-2.0 -isystem /home/conan/.conan/data/glib/2.75.2/_/_/package/02ae235820b1cc0e761686ccf0ced4cb8b458c83/lib/glib-2.0/include -isystem /home/conan/.conan/data/libmount/2.36.2/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/include -isystem /home/conan/.conan/data/libmount/2.36.2/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/include/libmount -isystem /home/conan/.conan/data/libselinux/3.3/_/_/package/3cdf9c40ed41ce093aec6e5f6607274047658b2d/include -isystem /home/conan/.conan/data/libelf/0.8.13/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/include -isystem /home/conan/.conan/data/libelf/0.8.13/_/_/package/1d877a3df840030e6a8abb74c5ffb9088d08b47a/include/libelf -isystem /home/conan/.conan/data/md4c/0.4.8/_/_/package/1f0857ade7461814b59ab8670ee33ac1589f95f3/include -isystem /home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtWidgets -isystem /home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtOpenGL -isystem /home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtOpenGLWidgets -m64 -Wall -Wextra -Wpedantic -Wcast-qual     -Wcast-align -Wredundant-decls -Wformat -Wshadow -Woverloaded-virtual     -fno-math-errno -funsafe-math-optimizations -O3 -DNDEBUG -fPIC -fPIC -std=c++11 -o CMakeFiles/qwt_objects.dir/qwt_magnifier.cpp.o -c /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/src/src/qwt_magnifier.cpp
In file included from /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/src/src/qwt_global.h:13,
                 from /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/src/src/qwt_interval_symbol.h:13,
                 from /home/conan/.conan/data/qwt/6.2.0/_/_/build/4438b4efa0b576ee9da17173dcdabefb23b64944/src/src/qwt_interval_symbol.cpp:10:
/home/conan/.conan/data/qt/6.3.0/_/_/package/37b79edf1f9287ae72a0010b85f7826c4d07ac12/include/QtCore/qglobal.h:125:6: error: #error "Qt requires a C++17 compiler"
 #    error "Qt requires a C++17 compiler"

I also try adding compiler.cppstd=17 to my profile, but there was not change

[ashley-b]

As a follow up I've found if I build qwt recipe locally with the following patch line removed, it builds successfully

conan-center-index/recipes/qwt/all/patches/cmake-support.patch

Line 116 in 7075441

+set(CMAKE_CXX_STANDARD 11)

[EstebanDugueperoux2]

Hi @ashley-b

I don't use anymore images from https://github.com/conan-io/conan-docker-tools#gcc but as recommended I use modern ones (https://github.com/conan-io/conan-docker-tools/tree/master/modern#gcc).

For information, qwt (https://qwt.sourceforge.io/) use qmake as build system, but to ease conan integration (https://github.com/conan-io/conan-center-index/tree/master/recipes/qwt/all) patches to use cmake has been added to replace qmake but only in conan center ().

Indeed "settings.compiler.cppstd" seems preferable to specify C++ standard instead of having it specified directly in CMAKE_CXX_STANDARD.

I think you can make a simple pull request to remove this CMAKE_CXX_STANDARD line.

Regards.