$NetBSD$

Always use pkgsrc SDL2.

--- CMakeLists.txt.orig	2023-02-09 19:13:05.000000000 +0000
+++ CMakeLists.txt
@@ -314,11 +314,7 @@ if(APPLE)
     set(MACOSX_BUNDLE_BUNDLE_VERSION "1.0.0")
 endif()
 
-if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Linux")
-    add_subdirectory("third_party/sdl2")
-else()
-    find_package(SDL2)
-endif()
+find_package(SDL2)
 
 add_subdirectory("third_party/fpattern")
 target_link_libraries(${EXECUTABLE_NAME} ${FPATTERN_LIBRARY})