diff --git a/.github/workflows/size-cmp.yml b/.github/workflows/size-cmp.yml
index df24fd60710..2d4053602d5 100644
--- a/.github/workflows/size-cmp.yml
+++ b/.github/workflows/size-cmp.yml
@@ -66,6 +66,7 @@ jobs:
         working-directory: current-pr/examples
         env:
           RUSTUP_TOOLCHAIN: nightly
+          RUSTFLAGS: --cfg nightly_yew
 
       - name: Collect size information
         run: python3 current-pr/ci/collect_sizes.py