cmake: define NDEBUG on the QuickJS library target

QuickJS asserts list_empty(rt->gc_obj_list) at the end of JS_FreeRuntime.
On embedders that legitimately have non-cycle-collected refs to JS values
held by long-lived native code, the cycle collector cannot break those
pins and the assertion aborts the process at shutdown. After the assert,
QuickJS' own fallback code in JS_FreeRuntime walks gc_obj_list itself and
frees what's still there, so disabling the assert is safe.

Define NDEBUG only on the qjs (and qjs-libc) targets so the rest of the
project keeps assertions enabled in Debug builds.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: CedricGuillemet

CMakeLists.txt

@@ -151,6 +151,18 @@ endif()
 if(NAPI_JAVASCRIPT_ENGINE STREQUAL "QuickJS")
     option(QJS_BUILD_LIBC "Build QuickJS with libc support." ON)
     FetchContent_MakeAvailable_With_Message(quickjs-ng)
+    # Always disable assert() inside the QuickJS library, including in Debug
+    # builds. QuickJS asserts that rt->gc_obj_list is empty in JS_FreeRuntime,
+    # which can fire on teardown when external (non-cycle-collected) refs from
+    # the embedder pin objects. Defining NDEBUG turns those asserts into no-ops
+    # and lets QuickJS's own free-everything fallback path run without aborting
+    # the process. This only affects the quickjs/qjs targets; our own code is
+    # still built with asserts enabled.
+    foreach(_qjs_target qjs qjs-libc)
+        if(TARGET ${_qjs_target})
+            target_compile_definitions(${_qjs_target} PRIVATE NDEBUG)
+        endif()
+    endforeach()
 endif()
 
 if(NAPI_JAVASCRIPT_ENGINE STREQUAL "V8" AND JSRUNTIMEHOST_CORE_APPRUNTIME_V8_INSPECTOR)