See if we can export SDL_main on Android

src/Bin/OpenEnroth/CMakeLists.txt

@@ -12,6 +12,7 @@ if(BUILD_PLATFORM STREQUAL "android")
     target_sources(main PUBLIC ${BIN_OPENENROTH_HEADERS} ${BIN_OPENENROTH_SOURCES})
     target_check_style(main)
     target_link_libraries(main PUBLIC application CLI11::CLI11)
+    target_link_options(main PRIVATE "-Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/libmain.map")
 else()
     add_executable(OpenEnroth MACOSX_BUNDLE)
     target_sources(OpenEnroth PUBLIC ${BIN_OPENENROTH_HEADERS} ${BIN_OPENENROTH_SOURCES})

src/Bin/OpenEnroth/libmain.map

@@ -0,0 +1,6 @@
+/* Linker script used when linking libmain.so for Android.
+ * Note that SDL_main is declared in SdlMain.cpp. */
+{
+  global: SDL_main;
+  local: *;
+};

src/Platform/Sdl/SdlMain.cpp

@@ -2,7 +2,8 @@
 
 int platformMain(int argc, char **argv);
 
-// This gets #defined by SDL into SDL_main.
-int main(int argc, char **argv) {
+// This gets #defined by SDL into SDL_main. Marking it as extern "C" is important for name mangling as on Android
+// it gets exported from the resulting .so.
+extern "C" int main(int argc, char **argv) {
     return platformMain(argc, argv);
 }