--- chromium-149.0.7827.53/v8/src/sandbox/testing.cc.orig	2026-05-28 16:24:11.000000000 -0700
+++ chromium-149.0.7827.53/v8/src/sandbox/testing.cc	2026-06-06 06:27:17.521326284 -0700
@@ -47,6 +47,16 @@
 #include "src/sandbox/external-strings-cage.h"
 #endif  // V8_ENABLE_SANDBOX && V8_ENABLE_MEMORY_CORRUPTION_API
 
+#ifdef V8_USE_ANY_SANITIZER
+// Some configurations define V8_USE_ANY_SANITIZER yet do not link a runtime
+// that provides sanitizer_common (e.g. official builds using CFI + ThinLTO but
+// no ASan/MSan). In that case __sanitizer_set_death_callback has no definition
+// and the link fails under -Wl,-z,defs. Provide a weak no-op fallback; the real
+// (strong) compiler-rt definition wins whenever a sanitizer runtime is linked.
+extern "C" __attribute__((weak)) void
+__sanitizer_set_death_callback(void (*callback)(void)) {}
+#endif  // V8_USE_ANY_SANITIZER
+
 namespace v8 {
 namespace internal {