diff --git a/.github/workflows/c.yml b/.github/workflows/c.yml
index 0340253..7ff1a9c 100644
--- a/.github/workflows/c.yml
+++ b/.github/workflows/c.yml
@@ -28,14 +28,12 @@ jobs:
     - name: Build
       env: 
         OPT_LEVEL: ${{ matrix.opt_level }}
+        ARCH: ${{ matrix.targetplatform }}
         TargetPlatform: ${{ matrix.targetplatform }}
       run: make
-    - name: SIKEp434 x64
-      if: ${{ matrix.targetplatform == 'x64' }}
-      run: make test434 ARCH=x64
-    - name: SIKEp434 x86
-      if: ${{ matrix.targetplatform == 'x86' }}
-      run: make test434 ARCH=x86
+    - name: SIKEp434
+      if: ${{ !(matrix.opt_level == 'FAST' && matrix.targetplatform == 'x86') }}
+      run: make test434
     - name: SIKEp503
       run: make test503
     - name: SIKEp610