diff --git a/projects/oak/build.sh b/projects/oak/build.sh
index 8a2720852..e68838b54 100755
--- a/projects/oak/build.sh
+++ b/projects/oak/build.sh
@@ -22,6 +22,7 @@ then
   export RUSTFLAGS="$RUSTFLAGS -C debug-assertions=no"
   chmod +x $SRC/rustc.py
   export RUSTC="$SRC/rustc.py"
+  export CFLAGS=""
 fi
 
 cargo fuzz build --release