[qt5-base] fails to build on mac runner "xcodebuild: error: SDK "/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk" cannot be located."

[ericfont]

I started a fresh clone of this and tried to use qt5-base but the runner reports:

https://github.com/ericfont/SerialAudio/runs/4172526046?check_suite_focus=true#step:5:1533

  Building package qt5-base[core]:x64-osx...
  -- Figuring out qt target mkspec. Target arch x64
  -- Target mkspec set to: macx-clang
  -- Host mkspec not set. Qt's own buildsystem will try to figure out the host system
  -- Downloading https://download.qt.io/official_releases/qt/5.15/5.15.2/submodules/qtbase-everywhere-src-5.15.2.tar.xz;https://mirrors.ocf.berkeley.edu/qt/official_releases/qt/5.15/5.15.2/submodules/qtbase-everywhere-src-5.15.2.tar.xz -> qtbase-everywhere-src-5.15.2.tar.xz...
  -- Extracting source /Users/runner/work/SerialAudio/SerialAudio/vcpkg/downloads/qtbase-everywhere-src-5.15.2.tar.xz
  -- Applying patch patches/winmain_pro.patch
  -- Applying patch patches/windows_prf.patch
  -- Applying patch patches/qt_app.patch
  -- Applying patch patches/gui_configure.patch
  -- Applying patch patches/icu.patch
  -- Applying patch patches/xlib.patch
  -- Applying patch patches/egl.patch
  -- Applying patch patches/zstdd.patch
  -- Applying patch patches/mysql_plugin_include.patch
  -- Applying patch patches/mysql-configure.patch
  -- Applying patch patches/Qt5BasicConfig.patch
  -- Applying patch patches/Qt5PluginTarget.patch
  -- Applying patch patches/create_cmake.patch
  -- Applying patch patches/Qt5GuiConfigExtras.patch
  -- Applying patch patches/limits_include.patch
  -- Using source at /Users/runner/work/SerialAudio/SerialAudio/vcpkg/buildtrees/qt5-base/src/5.15.2-fa8de595e1.clean
  xcodebuild: error: SDK "/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk" cannot be located.
  xcrun: error: unable to lookup item 'SDKVersion' in SDK '/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk'
  -- Detected OSX SDK Version: 
  CMake Error at ports/qt5-base/portfile.cmake:323 (string):
  Error:   string sub-command REGEX, mode MATCH needs at least 5 arguments total to

[ericfont]

actually the issues issue probably has nothing to do your with your github project. I also had issues with qt6 instead, both on win, linux, and mac. Seems like the os-latest virtual runners are not fully equipped to build and so I would need to install dependencies on them. In the meantime, I'm going to use a simpler gui library...

[ericfont]

amazingly the windows build of qt5-base succeed. https://github.com/ericfont/SerialAudio/runs/4172893334?check_suite_focus=true

[lukka]

@ericfont it must be a vcpkg issue, it looks similar if not identical to this open ticket: microsoft/vcpkg#14943