diff --git a/compiler/wasm32/cpuinfo.pas b/compiler/wasm32/cpuinfo.pas
index 250d951219..b054fac44b 100644
--- a/compiler/wasm32/cpuinfo.pas
+++ b/compiler/wasm32/cpuinfo.pas
@@ -94,7 +94,7 @@ Const
                                  [cs_opt_loopunroll,cs_opt_nodecse];
 
    level1optimizerswitches = genericlevel1optimizerswitches;
-   level2optimizerswitches = genericlevel2optimizerswitches + level1optimizerswitches + [cs_opt_nodecse];
+   level2optimizerswitches = genericlevel2optimizerswitches + level1optimizerswitches {+ [cs_opt_nodecse]};
    level3optimizerswitches = genericlevel3optimizerswitches + level2optimizerswitches;
    level4optimizerswitches = genericlevel4optimizerswitches + level3optimizerswitches + [];