With the latest version of Xcode (26.4.1) and CMake/Ninja, building AudioPluginHost and any other hosting project generates a warning - happens in both the master and develop branches:
[158/160] Building CXX object extras/AudioPluginHost/CMakeFiles/AudioPluginHost.dir/__/__/modules/juce_audio_processors_headless/juce_audio_processors_headless.mm.o
In file included from /Users/eyalamir/Code/JUCE/modules/juce_audio_processors_headless/juce_audio_processors_headless.mm:35:
In file included from /Users/eyalamir/Code/JUCE/modules/juce_audio_processors_headless/juce_audio_processors_headless.cpp:47:
In file included from /Users/eyalamir/Code/JUCE/modules/juce_audio_processors_headless/juce_audio_processors_headless.h:66:
In file included from /Users/eyalamir/Code/JUCE/modules/juce_audio_basics/juce_audio_basics.h:66:
In file included from /Users/eyalamir/Code/JUCE/modules/juce_core/juce_core.h:215:
In file included from /Users/eyalamir/Code/JUCE/modules/juce_core/system/juce_StandardHeader.h:68:
In file included from /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/v1/functional:601:
In file included from /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/v1/vector:363:
In file included from /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/v1/locale:203:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/v1/__locale_dir/wstring_convert.h:179:1: warning: 'wstring_convert<std::codecvt_utf8_utf16<char16_t>, char16_t>' is deprecated [-Wdeprecated-declarations]
179 | wstring_convert<_Codecvt, _Elem, _WideAlloc, _ByteAlloc>::to_bytes(const _Elem* __frm, const _Elem* __frm_end) {
| ^
/Users/eyalamir/Code/JUCE/modules/juce_audio_processors_headless/format_types/VST3_SDK/public.sdk/source/common/commonstringconvert.cpp:76:22: note: in instantiation of member function 'std::wstring_convert<std::codecvt_utf8_utf16<char16_t>, char16_t>::to_bytes' requested here
76 | return converter ().to_bytes (reinterpret_cast<const UTF16Type*> (str.data ()),
| ^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/v1/__locale_dir/wstring_convert.h:34:7: note: 'wstring_convert<std::codecvt_utf8_utf16<char16_t>, char16_t>' has been explicitly marked deprecated here
34 | class _LIBCPP_DEPRECATED_IN_CXX17 wstring_convert {
| ^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/v1/__config:581:41: note: expanded from macro '_LIBCPP_DEPRECATED_IN_CXX17'
581 | # define _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_DEPRECATED
| ^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/c++/v1/__config:554:49: note: expanded from macro '_LIBCPP_DEPRECATED'
554 | # define _LIBCPP_DEPRECATED __attribute__((__deprecated__))
| ^
1 warning generated.
[159/160] Linking CXX executable extras/AudioPluginHost/AudioPluginHost_artefacts/Debug/AudioPluginHost.app/Contents/MacOS/AudioPluginHost