Update Makefile

src/Makefile

@@ -127,7 +127,8 @@ endif
 # Define raylib release directory for compiled library
 RAYLIB_RELEASE_PATH 	?= $(RAYLIB_PATH)/src
 
-ifeq ($(PLATFORM),PLATFORM_WEB)
+ifeq ($(OS),Windows_NT)
+    ifeq ($(PLATFORM),PLATFORM_WEB)
         # Emscripten required variables
         EMSDK_PATH         ?= C:/emsdk
         EMSCRIPTEN_PATH    ?= $(EMSDK_PATH)/upstream/emscripten
@@ -135,6 +136,7 @@ ifeq ($(PLATFORM),PLATFORM_WEB)
         PYTHON_PATH         = $(EMSDK_PATH)/python/3.9.2-1_64bit
         NODE_PATH           = $(EMSDK_PATH)/node/14.15.5_64bit/bin
         export PATH         = $(EMSDK_PATH);$(EMSCRIPTEN_PATH);$(CLANG_PATH);$(NODE_PATH);$(PYTHON_PATH):$$(PATH)
+    endif
 endif
 
 # Define default C compiler: CC