diff --git a/projects/harfbuzz/build.sh b/projects/harfbuzz/build.sh
index e6af2420b..585c766b0 100755
--- a/projects/harfbuzz/build.sh
+++ b/projects/harfbuzz/build.sh
@@ -18,6 +18,7 @@
 # Disable:
 # 1. UBSan vptr since target built with -fno-rtti.
 export CFLAGS="$CFLAGS -fno-sanitize=function,vptr"
+export CXXFLAGS="$CXXFLAGS -fno-sanitize=function,vptr"
 
 # Build the library.
 ./autogen.sh