diff --git a/EffectLoad.cpp b/EffectLoad.cpp
index 05fced7..95e3509 100644
--- a/EffectLoad.cpp
+++ b/EffectLoad.cpp
@@ -1916,6 +1916,14 @@ HRESULT CEffectLoader::LoadAssignments( uint32_t Assignments, SAssignment **ppAs
             case ELHS_GeometryShaderSO:
                 assert(0); // Should never happen
 
+            #if (__cplusplus >= 201703L)
+                [[fallthrough]];
+            #elif defined(__clang__)
+                [[clang::fallthrough]];
+            #elif defined(_MSC_VER)
+                __fallthrough;
+            #endif
+
             default:
                 VHD( E_FAIL, "Internal loading error: invalid shader type."  );
             }
diff --git a/inc/d3dxGlobal.h b/inc/d3dxGlobal.h
index 2018c19..5d2bef2 100644
--- a/inc/d3dxGlobal.h
+++ b/inc/d3dxGlobal.h
@@ -680,7 +680,12 @@ static uint32_t ComputeHash(_In_reads_bytes_(cbToHash) const uint8_t *pb, _In_ u
 
     c += cbToHash;
 
-    switch(cbLeft) // all the case statements fall through
+#ifdef _PREFAST_
+#pragma prefast(push)
+#pragma prefast(disable:26819, "all the case statements fall through")
+#endif
+
+    switch(cbLeft)
     {
     case 11: c+=((uint32_t) pb[10] << 24);
     case 10: c+=((uint32_t) pb[9]  << 16);
@@ -696,6 +701,10 @@ static uint32_t ComputeHash(_In_reads_bytes_(cbToHash) const uint8_t *pb, _In_ u
     case 1 : a+=pb[0];
     }
 
+#ifdef _PREFAST_
+#pragma prefast(pop)
+#endif
+
     HASH_MIX(a,b,c);
 
     return c;
@@ -733,7 +742,12 @@ static uint32_t ComputeHashLower(_In_reads_bytes_(cbToHash) const uint8_t *pb, _
     for( size_t i = 0; i < cbLeft; i++ )
         pbT[i] = (uint8_t)tolower(pb[i]);
 
-    switch(cbLeft) // all the case statements fall through
+#ifdef _PREFAST_
+#pragma prefast(push)
+#pragma prefast(disable:26819, "all the case statements fall through")
+#endif
+
+    switch(cbLeft)
     {
     case 11: c+=((uint32_t) pbT[10] << 24);
     case 10: c+=((uint32_t) pbT[9]  << 16);
@@ -749,6 +763,10 @@ static uint32_t ComputeHashLower(_In_reads_bytes_(cbToHash) const uint8_t *pb, _
     case 1 : a+=pbT[0];
     }
 
+#ifdef _PREFAST_
+#pragma prefast(pop)
+#endif
+
     HASH_MIX(a,b,c);
 
     return c;