qvariant.cpp doesn't build with a mingw developer build

 FAILED: sccache C:\MINGW810\mingw64\bin\g++.exe -DCore_EXPORTS -DMINGW_HAS_SECURE_API=1 -DPCRE2_CODE_UNIT_WIDTH=16 -DPCRE2_STATIC -DQT_ASCII_CAST_WARNINGS -DQT_BUILDING_QT -DQT_BUILD_CORE_LIB -DQT_CORE_LIB -DQT_CORE_QOBJECT_LIB -DQT_DEPRECATED_WARNINGS -DQT_MOC_COMPAT -DQT_NO_DEBUG -DQT_NO_FOREACH -DQT_NO_USING_NAMESPACE -DQT_USE_QSTRINGBUILDER -DUNICODE -DWIN32 -DWIN64 -D_ENABLE_EXTENDED_ALIGNED_STORAGE -D_UNICODE -D_USE_MATH_DEFINES -D_WIN32_WINNT=0x0601 -D_WIN64 -Ddeprecations -Isrc/corelib/Core_autogen/include -Iinclude -Iinclude/QtCore -I/Users/qt/work/qt/qtbase/src/corelib -Isrc/corelib -Isrc/corelib/global -I/Users/qt/work/qt/qtbase/src/corelib/../3rdparty/tinycbor/src -Iinclude/QtCore/6.0.0 -Iinclude/QtCore/6.0.0/QtCore -I/Users/qt/work/qt/qtbase/src/corelib/../3rdparty/zlib/src -I/Users/qt/work/qt/qtbase/src/corelib/../3rdparty/double-conversion/.. -I/Users/qt/work/qt/qtbase/src/corelib/../3rdparty/double-conversion/include -Isrc/corelib/.rcc -I/Users/qt/work/qt/qtbase/mkspecs/win32-g++ -I/Users/qt/work/qt/qtbase/src/3rdparty/pcre2/src -g -DNDEBUG -O3 -fvisibility=hidden -fno-keep-inline-dllexport -Wall -Wextra -Werror -Wno-error=cpp -Wno-error=deprecated-declarations -Wno-error=strict-overflow -Wno-error=implicit-fallthrough -std=c++17 -Winvalid-pch -include C:/Users/qt/work/qt/qtbase/src/corelib/CMakeFiles/Core.dir/cmake_pch.hxx -MD -MT src/corelib/CMakeFiles/Core.dir/kernel/qvariant.cpp.obj -MF src\corelib\CMakeFiles\Core.dir\kernel\qvariant.cpp.obj.d -o src/corelib/CMakeFiles/Core.dir/kernel/qvariant.cpp.obj -c /Users/qt/work/qt/qtbase/src/corelib/kernel/qvariant.cpp
 /Users/qt/work/qt/qtbase/src/corelib/kernel/qvariant.cpp: In instantiation of 'int {anonymous}::spaceShip(Numeric, Numeric) [with Numeric = bool]':
 /Users/qt/work/qt/qtbase/src/corelib/kernel/qvariant.cpp:2290:38:   required from here
 /Users/qt/work/qt/qtbase/src/corelib/kernel/qvariant.cpp:2263:10: error: variable 'smaller' set but not used [-Werror=unused-but-set-variable]