sdl12-compat: BSD support: Don't assume presence of libdl on Unix

From 49e6ea8a8327a311edd5eddf3ebfd13da53b1cd5 Mon Sep 17 00:00:00 2001
From: nia <[EMAIL REDACTED]>
Date: Fri, 1 Apr 2022 09:08:43 +0200
Subject: [PATCH] BSD support: Don't assume presence of libdl on Unix

Most non-Linux OSes have dlopen() in libc, and CMake provides
a convenient variable for making use of libdl conditional.

Signed-off-by: Nia Alarie <nia@NetBSD.org>
---
 CMakeLists.txt | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0e96b6b..e7a847c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -71,7 +71,7 @@ string(STRIP "${CMAKE_C_FLAGS}" CMAKE_C_FLAGS)
 
 if(UNIX AND NOT APPLE)
     set_target_properties(SDL PROPERTIES COMPILE_DEFINITIONS "_REENTRANT")
-    target_link_libraries(SDL PRIVATE dl)
+    target_link_libraries(SDL PRIVATE ${CMAKE_DL_LIBS})
 endif()
 if(APPLE)
     set_target_properties(SDL PROPERTIES INSTALL_NAME_DIR "")
@@ -254,7 +254,7 @@ if(SDL12DEVEL)
       set(SDL_CFLAGS "-D_GNU_SOURCE=1 -D_REENTRANT")
       set(SDL_RLD_FLAGS "")  # !!! FIXME: this forces rpath, which we might want?
       set(SDL_LIBS "-lSDL")
-      set(SDL_STATIC_LIBS "-ldl")
+      set(SDL_STATIC_LIBS ${CMAKE_DL_LIBS})
       if(NOT STATICDEVEL)
         set(SDL_STATIC_LIBS "")
       endif()
@@ -297,7 +297,7 @@ if(STATICDEVEL AND SDL12DEVEL)
   add_library(SDL-static STATIC ${SDL12COMPAT_SRCS})
   target_include_directories(SDL-static PRIVATE ${SDL2_INCLUDE_DIRS})
   set_target_properties(SDL-static PROPERTIES COMPILE_DEFINITIONS "_REENTRANT")
-  target_link_libraries(SDL-static PRIVATE dl)
+  target_link_libraries(SDL-static PRIVATE ${CMAKE_DL_LIBS})
   set_target_properties(SDL-static PROPERTIES
           VERSION "${PROJECT_VERSION}"
         OUTPUT_NAME "SDL")