diff --git a/src/Makefile b/src/Makefile
index 2eaebe92..6ab17116 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -8,11 +8,11 @@ all: ../build/firmware/armv7-none-eabihf/release/szl
 	python zc706.py -r ../build/pl.rs
 
 ../build/firmware/armv7-none-eabihf/release/runtime: .cargo/* armv7-none-eabihf.json Cargo.lock Cargo.toml libdyld/* libdyld/src/* runtime/* runtime/src/* ../build/pl.rs
-	cargo xbuild --release -p runtime --target-dir ../build/firmware
+	XBUILD_SYSROOT_PATH=`pwd`/../build/sysroot cargo xbuild --release -p runtime --target-dir ../build/firmware
 
 ../build/szl-payload.bin.lzma: ../build/firmware/armv7-none-eabihf/release/runtime
 	llvm-objcopy -O binary ../build/firmware/armv7-none-eabihf/release/runtime ../build/szl-payload.bin
 	lzma --keep -f ../build/szl-payload.bin
 
 ../build/firmware/armv7-none-eabihf/release/szl: .cargo/* armv7-none-eabihf.json Cargo.lock Cargo.toml szl/* szl/src/* ../build/szl-payload.bin.lzma
-	cargo xbuild --release -p szl --target-dir ../build/firmware
+	XBUILD_SYSROOT_PATH=`pwd`/../build/sysroot cargo xbuild --release -p szl --target-dir ../build/firmware