Fix: Building on Haiku

CMakeLists.txt

@@ -241,6 +241,10 @@ target_link_libraries(openttd
     Threads::Threads
 )
 
+if(HAIKU)
+    target_link_libraries(openttd "be" "network" "midi")
+endif()
+
 if(IPO_FOUND)
     set_target_properties(openttd PROPERTIES INTERPROCEDURAL_OPTIMIZATION_RELEASE True)
     set_target_properties(openttd PROPERTIES INTERPROCEDURAL_OPTIMIZATION_MINSIZEREL True)

cmake/CompileFlags.cmake

@@ -158,7 +158,7 @@ macro(compile_flags)
         message(FATAL_ERROR "No warning flags are set for this compiler yet; please consider creating a Pull Request to add support for this compiler.")
     endif()
 
-    if(NOT WIN32)
+    if(NOT WIN32 AND NOT HAIKU)
         # rdynamic is used to get useful stack traces from crash reports.
         set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -rdynamic")
     endif()

src/music/CMakeLists.txt

@@ -34,7 +34,7 @@ if(NOT OPTION_DEDICATED)
     add_files(
         bemidi.cpp
         bemidi.h
-        CONDITION OPTION_HAIKU
+        CONDITION HAIKU
     )
 
     add_files(