From 6fc09121378d78026f799a820ce689f2d30bb0c9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9mi=20Verschelde?= <rverschelde@gmail.com>
Date: Thu, 15 Jun 2023 13:41:52 +0200
Subject: [PATCH] minimp3: Add a .cpp file to simplify building the
 single-header implementation

Single-header libraries like this require passing a bunch of defines _once_
before including the header, but not multiple times. This can make it tricky
in user code to know when to request the implementation, if the header needs
to be included in multiple files.

So properly compiling a .cpp file for the implementation solves this, and
also enables us to properly disable warnings on thirdparty implementation code.
---
 modules/minimp3/SCsub                | 28 +++++++++++++++++++++-------
 modules/minimp3/audio_stream_mp3.cpp |  5 -----
 thirdparty/README.md                 |  1 +
 thirdparty/minimp3/minimp3_ex.cpp    |  5 +++++
 4 files changed, 27 insertions(+), 12 deletions(-)
 create mode 100644 thirdparty/minimp3/minimp3_ex.cpp

diff --git a/modules/minimp3/SCsub b/modules/minimp3/SCsub
index 20e3165f38b..0f86ed5a88c 100644
--- a/modules/minimp3/SCsub
+++ b/modules/minimp3/SCsub
@@ -5,13 +5,27 @@ Import("env_modules")
 
 env_minimp3 = env_modules.Clone()
 
-thirdparty_dir = "#thirdparty/minimp3/"
+# Thirdparty source files
+
+thirdparty_obj = []
+
+thirdparty_dir = "#thirdparty/minimp3/"
+thirdparty_sources = [thirdparty_dir + "minimp3_ex.cpp"]
+
+env_minimp3.Prepend(CPPPATH=[thirdparty_dir])
+
+env_thirdparty = env_minimp3.Clone()
+env_thirdparty.disable_warnings()
+env_thirdparty.add_source_files(thirdparty_obj, thirdparty_sources)
+env.modules_sources += thirdparty_obj
 
-# Treat minimp3 headers as system headers to avoid raising warnings. Not supported on MSVC.
-if not env.msvc:
-    env_minimp3.Append(CPPFLAGS=["-isystem", Dir(thirdparty_dir).path])
-else:
-    env_minimp3.Prepend(CPPPATH=[thirdparty_dir])
 
 # Godot source files
-env_minimp3.add_source_files(env.modules_sources, "*.cpp")
+
+module_obj = []
+
+env_minimp3.add_source_files(module_obj, "*.cpp")
+env.modules_sources += module_obj
+
+# Needed to force rebuilding the module files when the thirdparty library is updated.
+env.Depends(module_obj, thirdparty_obj)
diff --git a/modules/minimp3/audio_stream_mp3.cpp b/modules/minimp3/audio_stream_mp3.cpp
index 6af86a96dcf..c63ec3cad05 100644
--- a/modules/minimp3/audio_stream_mp3.cpp
+++ b/modules/minimp3/audio_stream_mp3.cpp
@@ -28,11 +28,6 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
 /**************************************************************************/
 
-#define MINIMP3_ONLY_MP3
-#define MINIMP3_FLOAT_OUTPUT
-#define MINIMP3_IMPLEMENTATION
-#define MINIMP3_NO_STDIO
-
 #include "audio_stream_mp3.h"
 
 #include "core/io/file_access.h"
diff --git a/thirdparty/README.md b/thirdparty/README.md
index 0d5f3dd4c41..d34af58e8e6 100644
--- a/thirdparty/README.md
+++ b/thirdparty/README.md
@@ -416,6 +416,7 @@ Files extracted from upstream repository:
 
 Some changes have been made in order to fix Windows on ARM build errors, and
 to solve some MSVC warnings. See the patches in the `patches` directory.
+`minimp3_ex.cpp` was created to simplify the use of the single header library.
 
 
 ## miniupnpc
diff --git a/thirdparty/minimp3/minimp3_ex.cpp b/thirdparty/minimp3/minimp3_ex.cpp
new file mode 100644
index 00000000000..49c083e4f11
--- /dev/null
+++ b/thirdparty/minimp3/minimp3_ex.cpp
@@ -0,0 +1,5 @@
+#define MINIMP3_IMPLEMENTATION
+#define MINIMP3_FLOAT_OUTPUT
+#define MINIMP3_ONLY_MP3
+#define MINIMP3_NO_STDIO
+#include "minimp3_ex.h"