Fix LTO compilation with latest ld.lld on OSX

Author: TheBlueMatt

genbindings.sh

@@ -559,7 +559,8 @@ if [ "$CLANGPP" != "" -a "$LLD" != "" ]; then
 		CARGO_PROFILE_RELEASE_LTO=true RUSTFLAGS="$RUSTFLAGS -C embed-bitcode=yes -C linker-plugin-lto -C lto -C linker=$CLANG $LINK_ARG_FLAGS -C link-arg=-march=sandybridge -C link-arg=-mcpu=sandybridge -C link-arg=-mtune=sandybridge" cargo build $CARGO_BUILD_ARGS -v --release
 
 		if [ "$2" = "true" ]; then
-			$CLANGPP $LOCAL_CFLAGS -flto -fuse-ld=$LLD -O2 demo.cpp target/release/libldk.a -ldl
+			$CLANGPP $LOCAL_CFLAGS -flto -fuse-ld=$LLD -O2 -c demo.cpp -o demo.o
+			$CLANGPP $LOCAL_CFLAGS -flto -fuse-ld=$LLD -Wl,--lto-O2 -Wl,-O2 -O2 demo.o target/release/libldk.a -ldl
 			strip ./a.out
 			echo "C++ Bin size and runtime with cross-language LTO:"
 			ls -lha a.out