Build Qt from source for iOS arm64 simulator (on M1)

ad1170

Hi folks,
is it possible to build Qt6 (6.2.2) from source for the arm64 iOS simulator?

Generator Xcode:
Until now, the configure tool fails with the following error

error: unable to resolve product type 'com.apple.product-type.tool' for platform 'iphonesimulator' (in target 'architecture_test' from project 'arch')

I have made an additional makespec which set the arm64 for the simulator too.
The last try was to change the architecture test in the QtAutoDetect.cmake:210 to set(osx_architectures "arm64").
But it didn't help.

Trying to build x86_64 simulator also fails with the same message.
When is use the default (ninja) generator, the error message is

Could NOT find Qt6CoreTools (missing: Qt6CoreTools_DIR)

The Qt6CoreTools_DIR is set to ~/Qt/6.2.2/macos/lib/cmake/Qt6CoreTools

Here is the build script:

#!/bin/zsh
cd build

MY_QT_PATH=/Users/user/Qt/6.2.3
MY_ARCH=arm64

export PATH=/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/opt/homebrew/bin:/Library/Apple/usr/bin:/Users/user/Qt/Tools/CMake//CMake.app/Contents/MacOS/CMake:/Users/user/Qt/Tools/CMake/CMake.app/Contents/bin:/Users/user/Qt/Tools/Ninja

export QT_HOST_PATH=$MY_QT_PATH/Qt/6.2.2/macos
export QT_HOST_PATH_CMAKE_DIR=$MY_QT_PATH/macos/lib/cmake
export QT_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6

export CMAKE_OSX_ARCHITECTURES=$MY_ARCH
export CMAKE_OSX_SYSROOT=iphonesimulator
export CMAKE_PREFIX_PATH=$MY_QT_PATH/ios
export CMAKE_TOOLCHAIN_FILE=$MY_QT_PATH/ios/lib/cmake/Qt6/QtToolchainHelpers.cmake

export Qt6HostInfo_DIR=$MY_QT_PATH/macos/lib/cmake/Qt6HostInfo
export Qt6Bluetooth_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6Bluetooth
export Qt6BundledPcre2_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6BundledPcre2
export Qt6Concurrent_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6Concurrent
export Qt6CorePrivate_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6Core
export Qt6CoreTools_DIR=$MY_QT_PATH/macos/lib/cmake/Qt6CoreTools
export Qt6Core_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6Core
export Qt6EntryPointPrivate_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6EntryPointPrivate
export Qt6NetworkPrivate_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6Network
export Qt6Network_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6Network
export Qt6_DIR=$MY_QT_PATH/ios/lib/cmake/Qt6

../configure -platform macx-ios-clang-arm64 -DCMAKE_OSX_ARCHITECTURES=$MY_ARCH -release -prefix $MY_QT_PATH-Simulator-$MY_ARCH \ 
             -extprefix $MY_QT_PATH-Simulator-$MY_ARCH -cmake-generator Xcode -sdk iphonesimulator -qt-host-path $MY_QT_PATH/ios \ 
             -nomake tests -- -DCMAKE_OSX_ARCHITECTURES=$MY_ARCH -DQT_FORCE_MACOS_ALL_ARCHES_$MY_ARCH=TRUE -DCMAKE_SYSTEM_NAME=iOS \
             --trace-expand --trace-redirect=log.txt

Has anyone experience building qt 6 on mac?

Thanks.

ad1170

@ad1170 Meanwhile, we have solved the issue and fond a configuration that build Qt for iOS simulator for the arm64 and x86_64 architecture. The last solution is based on the qt-everywhere-src-6.2.3 and use the "macos" directory an installed Qt6.2.3 (via installer).

Install the Qt6.2.3 via the online installer
Download and extract the qt-everywhere-src-6.2.3 (https://download.qt.io/official_releases/qt/6.2/6.2.3/single/)
modify (or add a new) makespec for macx-ios-clang and add arm64 for the iOS simulator target (in qt-everywhere-src-6.2.3\qtbase\mkspecs)
make a build folder and change in to this folder
run the configure tool from qt-everywhere with following command line

YOUR_QT_DEST_PATH and PATH_TO_QT623 are placeholders, replace them according to your needs / environment.

../configure -release -static -xplatform macx-ios-clang -sdk iphonesimulator \
-prefix YOUR_QT_DEST_PATH -extprefix YOUR_QT_DEST_PATH -qt-host-path PATH_TO_QT623/macos \
-DCMAKE_OSX_SYSROOT="iphonesimulator" -- -DCMAKE_OSX_ARCHITECTURES="x86_64;arm64"

Run cmake --build . --parallel to build the Qt library's and cmake . --install to install this version in to your YOUR_QT_DEST_PATH.

Special thank goes to Patrick, he has made it possible.