From fc18fba11fd2b6ce13fa879576741f5eb05c7439 Mon Sep 17 00:00:00 2001
From: arekbr <arek@bronowicki.com>
Date: Wed, 5 Aug 2026 07:06:49 +0200
Subject: [PATCH] fix: macOS CI -- build static SDL2 from source, brew's sdl2
 is now sdl2-compat

The macOS job dies in MTEngineSDL's Libtool step:

  libtool: could not find 'libSDL2.a' for option -lSDL2

Root cause is outside the repo: Homebrew's 'sdl2' formula has become an alias
for sdl2-compat (a dynamic shim over SDL3) and no longer ships a static
libSDL2.a. The 'brew install sdl2' step (added in afbc20a, back when the
formula was real SDL2) still succeeds -- it just installs something else now.
The last green run was in June, before the formula switch; pinning the runner
image would not help, since homebrew-core is shared across images.

Fix: build static SDL2 2.32.10 from source in build-macos.sh and stage
libSDL2.a into MTEngineSDL/platform/MacOS/libs/ -- the exact pattern already
used for uSockets.a two lines above. With the file present, Xcode passes
libtool a full path (as it does for uSockets.a in the failing log), so nothing
depends on how the new Xcode 26.6 libtool resolves -L/-l. Success criterion in
the CI log: the Libtool command line shows .../libs/libSDL2.a as a full path
instead of -lSDL2.

The staging happens in build-macos.sh rather than the workflow because the
script clones MTEngineSDL only when the directory does not exist -- a workflow
step preparing that path first would skip the clone and break the build. Also
works for local developer builds, not just CI.
---
 .github/workflows/build-macos.yml | 12 ++++++------
 build-macos.sh                    | 18 ++++++++++++++++++
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/build-macos.yml b/.github/workflows/build-macos.yml
index 4ccc291..1b63660 100644
--- a/.github/workflows/build-macos.yml
+++ b/.github/workflows/build-macos.yml
@@ -15,12 +15,12 @@ jobs:
       - name: Checkout RetroDebugger
         uses: actions/checkout@v6
 
-      # SDL2 is the only external (Homebrew) dependency of the macOS build; it
-      # provides libSDL2.a, which the MTEngineSDL static lib merges in (libtool).
-      # llama.cpp / ftxui / mbedtls are built by MTEngineSDL's Xcode script phases,
-      # and uSockets is built by build-macos.sh — neither needs Homebrew here.
-      - name: Install macOS dependencies
-        run: brew install sdl2
+      # No Homebrew dependencies anymore. `brew install sdl2` used to provide
+      # libSDL2.a, but the formula is nowadays an alias for sdl2-compat (a dynamic
+      # shim over SDL3) which ships no static archive — the libtool step of
+      # MTEngineSDL then failed with "could not find 'libSDL2.a'". Static SDL2 is
+      # now built from source and staged by build-macos.sh, next to uSockets.a.
+      # llama.cpp / ftxui / mbedtls are built by MTEngineSDL's Xcode script phases.
 
       - name: Build and package release
         id: release
diff --git a/build-macos.sh b/build-macos.sh
index b31ca1a..573a1ac 100755
--- a/build-macos.sh
+++ b/build-macos.sh
@@ -30,6 +30,24 @@ echo "Building uSockets and staging uSockets.a for MTEngineSDL (macOS)"
 mkdir -p "$CURRENT_DIR/../MTEngineSDL/platform/MacOS/libs/"
 cp -f "$CURRENT_DIR/../uSockets/uSockets.a" "$CURRENT_DIR/../MTEngineSDL/platform/MacOS/libs/"
 
+# SDL2: Homebrew's "sdl2" formula is nowadays an alias for sdl2-compat (a dynamic
+# shim over SDL3) and no longer ships a static libSDL2.a, so `brew install sdl2`
+# stopped providing the archive MTEngineSDL's libtool step merges in. Build static
+# SDL2 from source and stage it next to uSockets.a — with the file present, Xcode
+# hands libtool a full path (same as uSockets.a) instead of relying on -L/-lSDL2.
+SDL2_VER=2.32.10
+SDL2_A="$CURRENT_DIR/../MTEngineSDL/platform/MacOS/libs/libSDL2.a"
+if [ ! -f "$SDL2_A" ]; then
+	echo "Building static SDL2 $SDL2_VER and staging libSDL2.a for MTEngineSDL (macOS)"
+	curl -fL -o "$CURRENT_DIR/../SDL2-src.tar.gz" "https://github.com/libsdl-org/SDL/releases/download/release-$SDL2_VER/SDL2-$SDL2_VER.tar.gz"
+	tar xzf "$CURRENT_DIR/../SDL2-src.tar.gz" -C "$CURRENT_DIR/.."
+	cmake -S "$CURRENT_DIR/../SDL2-$SDL2_VER" -B "$CURRENT_DIR/../sdl2-build" \
+		-DSDL_STATIC=ON -DSDL_SHARED=OFF -DSDL_TEST=OFF \
+		-DCMAKE_BUILD_TYPE=Release -DCMAKE_OSX_DEPLOYMENT_TARGET=10.15
+	cmake --build "$CURRENT_DIR/../sdl2-build" -j"$(sysctl -n hw.ncpu)"
+	cp -f "$CURRENT_DIR/../sdl2-build/libSDL2.a" "$SDL2_A"
+fi
+
 # --- build RetroDebugger via Xcode ---
 cd "$CURRENT_DIR"
 DERIVED="$CURRENT_DIR/build-macos"