Just silence the warning...

java/build_gcc.sh

@@ -19,7 +19,7 @@ sed -i -e 's/\.\/fixinc\.sh/-c true/' gcc/Makefile.in
 mkdir -p build; cd build
 
 # Configure source
-CFLAGS='-O2 -w' CXXFLAGS='-O2 -w' ../configure \
+CFLAGS='-w' CXXFLAGS='-w' ../configure \
     --prefix="$dir_install" \
     --disable-multilib \
     --disable-bootstrap \