harfbuzz-ng build failure

Trying to build webengine, but getting this in third-party. What could I easily do? This is 5.15.5:

../../../../Qt_src/qtwebengine/src/3rdparty/chromium/third_party/harfbuzz-ng/src/src/hb-subset-cff1.cc:408:33: error: variable 'supp_size' set but not used [-Werror,-Wunused-but-set-variable] unsigned int size0, size1, supp_size;

Compiler options: ... -isysroot ../../../../../../../../../../../../../../Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk -mmacosx-version-min=10.13 -fvisibility=hidden -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -Wall -Wno-unused-variable -Wno-misleading-indentation -Wunguarded-availability -Wno-missing-field-initializers -Wno-unused-parameter -Wno-c+11-narrowing -Wno-unneeded-internal-declaration -Wno-undefined-var-template -Wno-ignored-pragma-optimize -Wno-implicit-int-float-conversion -Wno-final-dtor-non-final-class -Wno-builtin-assume-aligned-alignment -Wno-deprecated-copy -Wno-non-c-typedef-for-linkage -Wno-pointer-to-int-cast -O3 -Wno-parentheses-equality -Wno-tautological-compare -Wno-undefined-bool-conversion -Wno-tautological-undefined-compare -std=c14 -stdlib=libc+ -fno-exceptions -fno-rtti -fvisibility-inlines-hidden -c ../../../../Qt_src/qtwebengine/src/3rdparty/chromium/third_party/harfbuzz-ng/src/src/hb-subset-cff1.cc -o obj/third_party/harfbuzz-ng/harfbuzz_source/hb-subset-cff1.o

Same issue as here: https://www.mail-archive.com/interest@qt-project.org/msg36740.html

Is there a way to build QtWebEngine without turning warnings into errors as a temporary workaround? Thanks.