SDL_mixer: cmake: add platforms supported by native midi to error message

From 2ceb67cf378d4eef0de7418a40e36fccfc0089f1 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Sat, 13 Jun 2026 09:09:58 +0200
Subject: [PATCH] cmake: add platforms supported by native midi to error
 message

---
 CMakeLists.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 55919d33..17a6078a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -140,7 +140,7 @@ option(SDL2MIXER_MIDI "Enable MIDI music" ON)
 cmake_dependent_option(SDL2MIXER_MIDI_FLUIDSYNTH "Support FluidSynth MIDI output" ON "SDL2MIXER_MIDI;NOT SDL2MIXER_VENDORED" OFF)
 cmake_dependent_option(SDL2MIXER_MIDI_FLUIDSYNTH_SHARED "Dynamically load libfluidsynth" "${SDL2MIXER_DEPS_SHARED}" SDL2MIXER_MIDI_FLUIDSYNTH OFF)
 
-if(WIN32 OR APPLE OR HAIKU)
+if(WIN32 OR APPLE OR HAIKU)  # keep in sync with error message
     cmake_dependent_option(SDL2MIXER_MIDI_NATIVE "Support native MIDI output" ON SDL2MIXER_MIDI OFF)
 else()
     set(SDL2MIXER_MIDI_NATIVE OFF)
@@ -149,7 +149,7 @@ endif()
 cmake_dependent_option(SDL2MIXER_MIDI_TIMIDITY "Support timidity MIDI output" ON SDL2MIXER_MIDI OFF)
 
 if(SDL2MIXER_MIDI AND NOT (SDL2MIXER_MIDI_TIMIDITY OR SDL2MIXER_MIDI_NATIVE OR SDL2MIXER_MIDI_FLUIDSYNTH))
-    message(FATAL_ERROR "MIDI support was enabled (SDL2MIXER_MIDI) but neither FluidSynth (SDL2MIXER_MIDI_FLUIDSYNTH), native (SDL2MIXER_MIDI_NATIVE) or timidity (SDL2MIXER_MIDI_TIMIDITY) was enabled")
+    message(FATAL_ERROR "MIDI support was enabled (SDL2MIXER_MIDI) but neither FluidSynth (SDL2MIXER_MIDI_FLUIDSYNTH), native (SDL2MIXER_MIDI_NATIVE) (limited to win32, apple & haiku) or timidity (SDL2MIXER_MIDI_TIMIDITY) was enabled.")
 endif()
 
 option(SDL2MIXER_OPUS "Enable Opus music" ON)