diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7ee3bc41..cbb3d4c5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -121,7 +121,7 @@ set(ZLIB_SRCS
 )
 
 if(NOT MINGW)
-    set(ZLIB_SRCS ${ZLIB_SRCS}
+    set(ZLIB_DLL_SRCS
         win32/zlib1.rc # If present will override custom build rule below.
     )
 endif()
@@ -134,7 +134,7 @@ string(REGEX REPLACE ".*#define[ \t]+ZLIB_VERSION[ \t]+\"([-0-9A-Za-z.]+)\".*"
 if(MINGW)
     # This gets us DLL resource information when compiling on MinGW.
     if(NOT CMAKE_RC_COMPILER)
-        SET(CMAKE_RC_COMPILER windres.exe)
+        set(CMAKE_RC_COMPILER windres.exe)
     endif()
 
     add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj
@@ -144,10 +144,10 @@ if(MINGW)
                             -I ${CMAKE_CURRENT_BINARY_DIR}
                             -o ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj
                             -i ${CMAKE_CURRENT_SOURCE_DIR}/win32/zlib1.rc)
-    set(ZLIB_SRCS ${ZLIB_SRCS} ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj)
+    set(ZLIB_DLL_SRCS ${CMAKE_CURRENT_BINARY_DIR}/zlib1rc.obj)
 endif(MINGW)
 
-add_library(zlib SHARED ${ZLIB_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
+add_library(zlib SHARED ${ZLIB_SRCS} ${ZLIB_DLL_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
 add_library(zlibstatic STATIC ${ZLIB_SRCS} ${ZLIB_PUBLIC_HDRS} ${ZLIB_PRIVATE_HDRS})
 set_target_properties(zlib PROPERTIES DEFINE_SYMBOL ZLIB_DLL)
 set_target_properties(zlib PROPERTIES SOVERSION 1)