diff --git a/mkspecs/features/wasm/wasm.prf b/mkspecs/features/wasm/wasm.prf
index 28f11251cab..2629e962c86 100644
--- a/mkspecs/features/wasm/wasm.prf
+++ b/mkspecs/features/wasm/wasm.prf
@@ -1,4 +1,5 @@
 
+QT_FOR_CONFIG += core-private
 
 # DESTDIR will be empty if not set in the app .pro file; make sure it has a value
 isEmpty(DESTDIR): DESTDIR = $$OUT_PWD
@@ -37,6 +38,13 @@ exists($$QMAKE_QT_CONFIG) {
             EMCC_THREAD_LFLAGS += -s INITIAL_MEMORY=$$INITIAL_MEMORY
     }
 
+    qtConfig(sse2) {
+        QMAKE_CFLAGS += -O2 -msimd128 -msse -msse2
+        QMAKE_CXXFLAGS += -O2 -msimd128 -msse -msse2
+        QMAKE_LFLAGS       += -msimd128 -msse -msse2
+        QMAKE_LFLAGS_DEBUG += -msimd128 -msse -msse2
+    }
+
     QMAKE_LFLAGS       += $$EMCC_THREAD_LFLAGS
     QMAKE_LFLAGS_DEBUG += $$EMCC_THREAD_LFLAGS
     QMAKE_CFLAGS += $$EMCC_THREAD_LFLAGS