Qt6 support status - Githubissues

The plugin needs to be compiled against app's Qt version. I'm idiot on cmake, yet I modified a version that works under my distro. May help someone wants it on Qt6, hope official support
cmake_minimum_required(VERSION 3.5)  # lowest version tried

set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

# make release build, if not specified
# (from https://blog.kitware.com/cmake-and-the-default-build-type/)
set(default_build_type "RelWithDebInfo")

if (NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
  set(CMAKE_BUILD_TYPE "${default_build_type}" CACHE STRING "Build type" FORCE)
  set_property(
    CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
    "Debug" "Release" "MinSizeRel" "RelWithDebInfo")
endif ()

# compiler flags
# TODO: separate GCC and Clang warnings; add more
set(
  CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} \
  -Wall \
  -Wextra \
  -Wshadow \
  -Wformat-nonliteral \
  -Wformat-security \
  -Wnon-virtual-dtor \
  ")

set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -Og")

set(sanitizer_flags "-fsanitize=address -fsanitize=undefined")
set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} ${sanitizer_flags}")
set(CMAKE_MODULE_LINKER_FLAGS_DEBUG
    "${CMAKE_MODULE_LINKER_FLAGS_DEBUG} ${sanitizer_flags}")

#
# third-party libs
#

# qt
find_package(Qt6 COMPONENTS Core Gui REQUIRED)
add_definitions(-DQT_NO_KEYWORDS)
set(CMAKE_AUTOMOC ON)

# libheif
find_package(PkgConfig)
pkg_check_modules(libheif REQUIRED libheif>=1.1)

#
# project source
#

set(CMAKE_INCLUDE_CURRENT_DIR ON)

set(sources main.cpp qheifhandler.cpp)

add_library(qheif MODULE ${sources})

target_link_libraries(
  qheif
  PRIVATE
  Qt6::Gui
  ${libheif_LIBRARIES}
)

#
# installation
#

# Use qmake to find plugin dir (adapted from lxqt-qtplugin)
#get_target_property(
#  QT_QMAKE_EXECUTABLE ${Qt6Core_QMAKE_EXECUTABLE} IMPORTED_LOCATION)
set(QT_QMAKE_EXECUTABLE /usr/bin/qmake6)

if (NOT QT_QMAKE_EXECUTABLE)
  message(FATAL_ERROR "qmake is not found.")
endif ()

execute_process(
  COMMAND ${QT_QMAKE_EXECUTABLE} -query QT_INSTALL_PLUGINS
  OUTPUT_VARIABLE QT_PLUGINS_DIR
  OUTPUT_STRIP_TRAILING_WHITESPACE)

if (QT_PLUGINS_DIR)
  message(STATUS "Qt6 plugin directory: " "${QT_PLUGINS_DIR}")
else ()
  message(FATAL_ERROR "Qt6 plugin directory cannot be detected.")
endif ()

# Prefix with DESTDIR if available to allow packaging
if (ENV{DESTDIR} AND NOT ENV{DESTDIR} STREQUAL "")
  set(plugins_dir "$ENV{DESTDIR}${QT_PLUGINS_DIR}")
else ()
  set(plugins_dir "${QT_PLUGINS_DIR}")
endif ()

install(
  TARGETS qheif
  LIBRARY DESTINATION "${plugins_dir}/imageformats")

# vim:sw=2
jakar / qt-heif-image-plugin

Qt6 support status #27
