[libunwind] Undefined behaviour pointer arithmetic with null pointer …

…(#98648) Fixes #91144
intel · Aug 5, 2024 · 710590e · 710590e
1 parent dd8a9e2
commit 710590e
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/libunwind/src/UnwindCursor.hpp b/libunwind/src/UnwindCursor.hpp
@@ -230,8 +230,8 @@ void DwarfFDECache<A>::iterateCacheEntries(void (*func)(
 }
 #endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
 
-
-#define arrayoffsetof(type, index, field) ((size_t)(&((type *)0)[index].field))
+#define arrayoffsetof(type, index, field)                                      \
+  (sizeof(type) * (index) + offsetof(type, field))
 
 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND)
 template <typename A> class UnwindSectionHeader {