diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4a978dd..e7abd57 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -454,6 +454,9 @@ endif()
 if(PNG_FOUND)
   target_include_directories(simage PRIVATE ${PNG_INCLUDE_DIR})
   target_link_libraries(simage PRIVATE ${PNG_LIBRARIES})
+  if(UNIX)
+    target_link_libraries(simage PRIVATE m)
+  endif()
 endif()
 
 if(SIMAGE_QIMAGE_SUPPORT)