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The g_wasm_ctx global (BSS-resident, initialized to NULL) was lost across Emscripten's main-loop unwind transition when emscripten_set_main_loop_arg() exits main() via throw "unwind" with -sASYNCIFY. This caused all exported input injection functions (iui_wasm_mouse_button, iui_wasm_mouse_motion, etc.) called from JavaScript event handlers to silently bail out, making mouse interaction non-functional. The ctx pointer passed through the port function table remains valid (heap-allocated via calloc), so re-establish g_wasm_ctx at the start of wasm_poll_events() each frame before JS event callbacks can reference it.
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The g_wasm_ctx global (BSS-resident, initialized to NULL) was lost across Emscripten's main-loop unwind transition when emscripten_set_main_loop_arg() exits main() via throw "unwind" with
-sASYNCIFY. This caused all exported input injection functions (iui_wasm_mouse_button,iui_wasm_mouse_motion, etc.) called from JavaScript event handlers to silently bail out, making mouse interaction non-functional.The ctx pointer passed through the port function table remains valid (heap-allocated via calloc), so re-establish
g_wasm_ctxat the start ofwasm_poll_events()each frame before JS event callbacks can reference it.Summary by cubic
Restore mouse input in WASM by re-establishing g_wasm_ctx at the start of each frame in wasm_poll_events. This fixes the lost global after Emscripten’s ASYNCIFY main-loop unwind, which caused JS-driven input functions to no-op.
Written for commit d89db97. Summary will update on new commits.