diff --git a/Makefile b/Makefile
index eac0a1c..ee3f85a 100644
--- a/Makefile
+++ b/Makefile
@@ -557,9 +557,13 @@ all: $(TARGET)
 
 ifeq ($(DEBUG),1)
    FLAGS += -O0 -g
+else
+ifeq ($(platform), emscripten)
+   FLAGS += -O3 -DNDEBUG $(EXTRA_GCC_FLAGS)
 else
    FLAGS += -O2 -DNDEBUG $(EXTRA_GCC_FLAGS)
 endif
+endif
 
 ifneq (,$(findstring msvc,$(platform)))
 ifeq ($(DEBUG),1)
@@ -597,9 +601,7 @@ else
 endif
 
 $(TARGET): $(OBJECTS)
-ifeq ($(platform), emscripten)
-	$(CXX) $(CXXFLAGS) $(OBJOUT)$@ $^
-else ifeq ($(STATIC_LINKING), 1)
+ifeq ($(STATIC_LINKING), 1)
 	$(AR) rcs $@ $(OBJECTS)
 else
 	$(LD) $(LINKOUT)$@ $^ $(LDFLAGS)