build steps

CMakeLists.txt

@@ -9,7 +9,14 @@ option(LEANCLR_GODOT_FETCH_GODOT_CPP "Fetch godot-cpp when GODOT_CPP_ROOT is not
 set(GODOT_CPP_ROOT "" CACHE PATH "Path to a checked-out godot-cpp tree")
 set(GODOT_CPP_LIBRARY "" CACHE FILEPATH "Path to a prebuilt godot-cpp static library. When set, godot-cpp is imported instead of built.")
 set(GODOT_CPP_GEN_INCLUDE_DIR "" CACHE PATH "Path to godot-cpp generated headers, for example <godot-cpp-build>/gen/include")
-set(GODOT_CPP_BRANCH "4.4" CACHE STRING "godot-cpp branch or tag to use when fetching")
+set(GODOT_CPP_BRANCH "4.5" CACHE STRING "godot-cpp branch or tag to use when fetching")
+
+# Only the Web build is single-threaded today — pthreads in a wasm side
+# module is experimental and the demo does not need it. Forward to godot-cpp
+# so its own -sUSE_PTHREADS=1 (see godot-cpp/cmake/web.cmake) is not emitted.
+if(EMSCRIPTEN)
+    set(GODOTCPP_THREADS OFF CACHE BOOL "godot-cpp threading support" FORCE)
+endif()
 
 if(MSVC)
     set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreadedDLL" CACHE STRING "Select the MSVC runtime library for GDExtension binaries." FORCE)
@@ -119,6 +126,12 @@ endif()
 if(EMSCRIPTEN)
     target_link_options(leanclr_godot PRIVATE -sSIDE_MODULE=1)
     set_target_properties(leanclr_godot PROPERTIES SUFFIX ".wasm")
+    # The auto-generated godot_api.generated.cpp has thousands of invoker
+    # functions; at -O3 the compiler inlines argument unpacking and blows
+    # past V8's 50,000-locals-per-function limit ("local count too large" at
+    # runtime). Cap the web build at -O1 to keep each function's locals
+    # manageable.
+    target_compile_options(leanclr_godot PRIVATE -O1)
 endif()
 
 set_target_properties(leanclr_godot PROPERTIES