libcxxabi: Update to LLVM 19.

lib/libcxxabi/include/cxxabi.h

@@ -48,13 +48,17 @@ extern _LIBCXXABI_FUNC_VIS void
 __cxa_free_exception(void *thrown_exception) throw();
 // This function is an LLVM extension, which mirrors the same extension in libsupc++ and libcxxrt
 extern _LIBCXXABI_FUNC_VIS __cxa_exception*
+#ifdef __wasm__
+// In Wasm, a destructor returns its argument
+__cxa_init_primary_exception(void* object, std::type_info* tinfo, void*(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw();
+#else
 __cxa_init_primary_exception(void* object, std::type_info* tinfo, void(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw();
+#endif
 
 // 2.4.3 Throwing the Exception Object
 extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_NORETURN void
 __cxa_throw(void *thrown_exception, std::type_info *tinfo,
-#ifdef __USING_WASM_EXCEPTIONS__
+#ifdef __wasm__
-            // In Wasm, a destructor returns its argument
             void *(_LIBCXXABI_DTOR_FUNC *dest)(void *));
 #else
             void (_LIBCXXABI_DTOR_FUNC *dest)(void *));
@@ -73,6 +77,11 @@ extern _LIBCXXABI_FUNC_VIS void __cxa_end_cleanup();
 #endif
 extern _LIBCXXABI_FUNC_VIS std::type_info *__cxa_current_exception_type();
 
+// GNU extension
+// Calls `terminate` with the current exception being caught. This function is used by GCC when a `noexcept` function
+// throws an exception inside a try/catch block and doesn't catch it.
+extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_NORETURN void __cxa_call_terminate(void*) throw();
+
 // 2.5.4 Rethrowing Exceptions
 extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_NORETURN void __cxa_rethrow();
 

lib/libcxxabi/src/aix_state_tab_eh.inc

@@ -102,8 +102,6 @@ static bool state_tab_dbg() {
 
 namespace __state_table_eh {
 
-using destruct_f = void (*)(void*);
-
 // Definition of flags for the state table entry field 'action flag'.
 enum FSMEntryCount : intptr_t { beginCatch = -1, endCatch = -2, deleteObject = -3, cleanupLabel = -4, terminate = -5 };
 
@@ -145,8 +143,10 @@ struct FSMEntry {
     intptr_t nextStatePtr;
   };
   union {
-    // Address of the destructor function.
+    // Address of the destructor function with 1 argument.
-    void (*destructor)(void*, size_t);
+    void (*destructor)(void*);
+    // Address of the destructor function with 2 arguments.
+    void (*xlCDestructor)(void*, size_t);
     // The address of the catch block or cleanup code.
     void* landingPad;
   };
@@ -191,12 +191,12 @@ static void invoke_destructor(FSMEntry* fsmEntry, void* addr) {
   try {
     if (fsmEntry->elementCount == 1) {
       _LIBCXXABI_TRACE_STATETAB0("calling scalar destructor\n");
-      (*fsmEntry->destructor)(addr, dtorArgument);
+      (*fsmEntry->xlCDestructor)(addr, dtorArgument);
       _LIBCXXABI_TRACE_STATETAB0("returned from scalar destructor\n");
     } else {
       _LIBCXXABI_TRACE_STATETAB0("calling vector destructor\n");
       __cxa_vec_cleanup(addr, reinterpret_cast<size_t>(fsmEntry->elementCount), fsmEntry->elemSize,
-                        reinterpret_cast<destruct_f>(fsmEntry->destructor));
+                        fsmEntry->destructor);
       _LIBCXXABI_TRACE_STATETAB0("returned from vector destructor\n");
     }
   } catch (...) {
@@ -213,7 +213,7 @@ static void invoke_delete(FSMEntry* fsmEntry, void* addr) {
   try {
     _LIBCXXABI_TRACE_STATETAB0("..calling delete()\n");
     // 'destructor' holds a function pointer to delete().
-    (*fsmEntry->destructor)(objectAddress, fsmEntry->elemSize);
+    (*fsmEntry->xlCDestructor)(objectAddress, fsmEntry->elemSize);
     _LIBCXXABI_TRACE_STATETAB0("..returned from delete()\n");
   } catch (...) {
     _LIBCXXABI_TRACE_STATETAB0("Uncaught exception in delete(), terminating\n");
@@ -681,7 +681,7 @@ static uintptr_t* skip_non_cxx_eh_aware_frames(uint32_t* Pc, uintptr_t* Sp) {
 // xlclang++ compiled code. If __xlc_exception_handle() is called by
 // non-C++ EH aware functions, their frames are skipped until a C++ EH aware
 // frame is found.
-// Note: make sure __xlc_excpetion_handle() is a non-leaf function. Currently
+// Note: make sure __xlc_exception_handle() is a non-leaf function. Currently
 // it calls skip_non_cxx_eh_aware_frames(), which in turn calls abort().
 _LIBCXXABI_FUNC_VIS uintptr_t __xlc_exception_handle() {
   // Get the SP of this function, i.e., __xlc_exception_handle().

lib/libcxxabi/src/cxa_exception.cpp

@@ -207,7 +207,12 @@ void __cxa_free_exception(void *thrown_object) throw() {
 }
 
 __cxa_exception* __cxa_init_primary_exception(void* object, std::type_info* tinfo,
+#ifdef __wasm__
+// In Wasm, a destructor returns its argument
+                                              void *(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw() {
+#else
                                               void(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw() {
+#endif
   __cxa_exception* exception_header = cxa_exception_from_thrown_object(object);
   exception_header->referenceCount = 0;
   exception_header->unexpectedHandler = std::get_unexpected();
@@ -267,7 +272,7 @@ will call terminate, assuming that there was no handler for the
 exception.
 */
 void
-#ifdef __USING_WASM_EXCEPTIONS__
+#ifdef __wasm__
 // In Wasm, a destructor returns its argument
 __cxa_throw(void *thrown_object, std::type_info *tinfo, void *(_LIBCXXABI_DTOR_FUNC *dest)(void *)) {
 #else
@@ -584,6 +589,11 @@ void __cxa_end_catch() {
     }
 }
 
+void __cxa_call_terminate(void* unwind_arg) throw() {
+  __cxa_begin_catch(unwind_arg);
+  std::terminate();
+}
+
 // Note:  exception_header may be masquerading as a __cxa_dependent_exception
 //        and that's ok.  exceptionType is there too.
 //        However watch out for foreign exceptions.  Return null for them.

lib/libcxxabi/src/cxa_exception.h

@@ -43,7 +43,7 @@ struct _LIBCXXABI_HIDDEN __cxa_exception {
 
     //  Manage the exception object itself.
     std::type_info *exceptionType;
-#ifdef __USING_WASM_EXCEPTIONS__
+#ifdef __wasm__
     // In Wasm, a destructor returns its argument
     void *(_LIBCXXABI_DTOR_FUNC *exceptionDestructor)(void *);
 #else

lib/libcxxabi/src/cxa_exception_storage.cpp

@@ -12,7 +12,7 @@
 
 #include "cxa_exception.h"
 
-#include <__threading_support>
+#include <__thread/support.h>
 
 #if defined(_LIBCXXABI_HAS_NO_THREADS)
 
@@ -24,7 +24,7 @@ extern "C" {
 } // extern "C"
 } // namespace __cxxabiv1
 
-#elif defined(HAS_THREAD_LOCAL)
+#elif __has_feature(cxx_thread_local)
 
 namespace __cxxabiv1 {
 namespace {

lib/libcxxabi/src/cxa_guard_impl.h

@@ -58,7 +58,7 @@
 #  endif
 #endif
 
-#include <__threading_support>
+#include <__thread/support.h>
 #include <cstdint>
 #include <cstring>
 #include <limits.h>

lib/libcxxabi/src/cxa_personality.cpp

@@ -70,7 +70,7 @@ extern "C" EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD,
 +------------------+--+-----+-----+------------------------+--------------------------+
 | callSiteTableLength | (ULEB128) | Call Site Table length, used to find Action table |
 +---------------------+-----------+---------------------------------------------------+
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__USING_WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
 +---------------------+-----------+------------------------------------------------+
 | Beginning of Call Site Table            The current ip lies within the           |
 | ...                                     (start, length) range of one of these    |
@@ -84,7 +84,7 @@ extern "C" EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD,
 | +-------------+---------------------------------+------------------------------+ |
 | ...                                                                              |
 +----------------------------------------------------------------------------------+
-#else  // __USING_SJLJ_EXCEPTIONS__ || __USING_WASM_EXCEPTIONS__
+#else  // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
 +---------------------+-----------+------------------------------------------------+
 | Beginning of Call Site Table            The current ip is a 1-based index into   |
 | ...                                     this table.  Or it is -1 meaning no      |
@@ -97,7 +97,7 @@ extern "C" EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD,
 | +-------------+---------------------------------+------------------------------+ |
 | ...                                                                              |
 +----------------------------------------------------------------------------------+
-#endif // __USING_SJLJ_EXCEPTIONS__ || __USING_WASM_EXCEPTIONS__
+#endif // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
 +---------------------------------------------------------------------+
 | Beginning of Action Table       ttypeIndex == 0 : cleanup           |
 | ...                             ttypeIndex  > 0 : catch             |
@@ -547,7 +547,7 @@ void
 set_registers(_Unwind_Exception* unwind_exception, _Unwind_Context* context,
               const scan_results& results)
 {
-#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__USING_WASM_EXCEPTIONS__)
+#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__WASM_EXCEPTIONS__)
 #define __builtin_eh_return_data_regno(regno) regno
 #elif defined(__ibmxl__)
 // IBM xlclang++ compiler does not support __builtin_eh_return_data_regno.
@@ -642,7 +642,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     // Get beginning current frame's code (as defined by the
     // emitted dwarf code)
     uintptr_t funcStart = _Unwind_GetRegionStart(context);
-#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__USING_WASM_EXCEPTIONS__)
+#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__WASM_EXCEPTIONS__)
     if (ip == uintptr_t(-1))
     {
         // no action
@@ -652,9 +652,9 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     else if (ip == 0)
         call_terminate(native_exception, unwind_exception);
     // ip is 1-based index into call site table
-#else  // !__USING_SJLJ_EXCEPTIONS__ && !__USING_WASM_EXCEPTIONS__
+#else  // !__USING_SJLJ_EXCEPTIONS__ && !__WASM_EXCEPTIONS__
     uintptr_t ipOffset = ip - funcStart;
-#endif // !__USING_SJLJ_EXCEPTIONS__ && !__USING_WASM_EXCEPTIONS__
+#endif // !__USING_SJLJ_EXCEPTIONS__ && !__WASM_EXCEPTIONS__
     const uint8_t* classInfo = NULL;
     // Note: See JITDwarfEmitter::EmitExceptionTable(...) for corresponding
     //       dwarf emission
@@ -675,7 +675,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     // Walk call-site table looking for range that
     // includes current PC.
     uint8_t callSiteEncoding = *lsda++;
-#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__USING_WASM_EXCEPTIONS__)
+#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__WASM_EXCEPTIONS__)
     (void)callSiteEncoding;  // When using SjLj/Wasm exceptions, callSiteEncoding is never used
 #endif
     uint32_t callSiteTableLength = static_cast<uint32_t>(readULEB128(&lsda));
@@ -686,7 +686,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     while (callSitePtr < callSiteTableEnd)
     {
         // There is one entry per call site.
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__USING_WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
         // The call sites are non-overlapping in [start, start+length)
         // The call sites are ordered in increasing value of start
         uintptr_t start = readEncodedPointer(&callSitePtr, callSiteEncoding);
@@ -694,15 +694,15 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
         uintptr_t landingPad = readEncodedPointer(&callSitePtr, callSiteEncoding);
         uintptr_t actionEntry = readULEB128(&callSitePtr);
         if ((start <= ipOffset) && (ipOffset < (start + length)))
-#else  // __USING_SJLJ_EXCEPTIONS__ || __USING_WASM_EXCEPTIONS__
+#else  // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
         // ip is 1-based index into this table
         uintptr_t landingPad = readULEB128(&callSitePtr);
         uintptr_t actionEntry = readULEB128(&callSitePtr);
         if (--ip == 0)
-#endif // __USING_SJLJ_EXCEPTIONS__ || __USING_WASM_EXCEPTIONS__
+#endif // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
         {
             // Found the call site containing ip.
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__USING_WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
             if (landingPad == 0)
             {
                 // No handler here
@@ -710,16 +710,14 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
                 return;
             }
             landingPad = (uintptr_t)lpStart + landingPad;
-#else  // __USING_SJLJ_EXCEPTIONS__ || __USING_WASM_EXCEPTIONS__
+#else  // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
             ++landingPad;
-#endif // __USING_SJLJ_EXCEPTIONS__ || __USING_WASM_EXCEPTIONS__
+#endif // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
             results.landingPad = landingPad;
             if (actionEntry == 0)
             {
                 // Found a cleanup
-                results.reason = actions & _UA_SEARCH_PHASE
+                results.reason = (actions & _UA_SEARCH_PHASE) ? _URC_CONTINUE_UNWIND : _URC_HANDLER_FOUND;
-                                     ? _URC_CONTINUE_UNWIND
-                                     : _URC_HANDLER_FOUND;
                 return;
             }
             // Convert 1-based byte offset into
@@ -840,7 +838,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
                 action += actionOffset;
             }  // there is no break out of this loop, only return
         }
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__USING_WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
         else if (ipOffset < start)
         {
             // There is no call site for this ip
@@ -848,7 +846,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
             // Possible stack corruption.
             call_terminate(native_exception, unwind_exception);
         }
-#endif // !__USING_SJLJ_EXCEPTIONS__ && !__USING_WASM_EXCEPTIONS__
+#endif // !__USING_SJLJ_EXCEPTIONS__ && !__WASM_EXCEPTIONS__
     }  // there might be some tricky cases which break out of this loop
 
     // It is possible that no eh table entry specify how to handle
@@ -905,7 +903,7 @@ _UA_CLEANUP_PHASE
 */
 
 #if !defined(_LIBCXXABI_ARM_EHABI)
-#ifdef __USING_WASM_EXCEPTIONS__
+#ifdef __WASM_EXCEPTIONS__
 _Unwind_Reason_Code __gxx_personality_wasm0
 #elif defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
 static _Unwind_Reason_Code __gxx_personality_imp
@@ -974,7 +972,7 @@ __gxx_personality_v0
             exc->languageSpecificData = results.languageSpecificData;
             exc->catchTemp = reinterpret_cast<void*>(results.landingPad);
             exc->adjustedPtr = results.adjustedPtr;
-#ifdef __USING_WASM_EXCEPTIONS__
+#ifdef __WASM_EXCEPTIONS__
             // Wasm only uses a single phase (_UA_SEARCH_PHASE), so save the
             // results here.
             set_registers(unwind_exception, context, results);

lib/libcxxabi/src/cxa_thread_atexit.cpp

@@ -8,7 +8,7 @@
 
 #include "abort_message.h"
 #include "cxxabi.h"
-#include <__threading_support>
+#include <__thread/support.h>
 #ifndef _LIBCXXABI_HAS_NO_THREADS
 #if defined(__ELF__) && defined(_LIBCXXABI_LINK_PTHREAD_LIB)
 #pragma comment(lib, "pthread")

lib/libcxxabi/src/demangle/ItaniumDemangle.h

@@ -39,13 +39,12 @@
 DEMANGLE_NAMESPACE_BEGIN
 
 template <class T, size_t N> class PODSmallVector {
-  static_assert(std::is_pod<T>::value,
+  static_assert(std::is_trivial<T>::value,
-                "T is required to be a plain old data type");
+                "T is required to be a trivial type");
-
   T *First = nullptr;
   T *Last = nullptr;
   T *Cap = nullptr;
-  T Inline[N] = {0};
+  T Inline[N] = {};
 
   bool isInline() const { return First == Inline; }
 
@@ -5542,7 +5541,7 @@ Node *AbstractManglingParser<Alloc, Derived>::parseFloatingLiteral() {
     return nullptr;
   std::string_view Data(First, N);
   for (char C : Data)
-    if (!std::isxdigit(C))
+    if (!(C >= '0' && C <= '9') && !(C >= 'a' && C <= 'f'))
       return nullptr;
   First += N;
   if (!consumeIf('E'))
@@ -5716,6 +5715,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseTemplateParam() {
 }
 
 // <template-param-decl> ::= Ty                          # type parameter
+//                       ::= Tk <concept name> [<template-args>] # constrained type parameter
 //                       ::= Tn <type>                   # non-type parameter
 //                       ::= Tt <template-param-decl>* E # template parameter
 //                       ::= Tp <template-param-decl>    # parameter pack
@@ -5847,7 +5847,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parseTemplateArg() {
   }
 }
 
-// <template-args> ::= I <template-arg>* E
+// <template-args> ::= I <template-arg>* [Q <requires-clause expr>] E
 //     extension, the abi says <template-arg>+
 template <typename Derived, typename Alloc>
 Node *

lib/libcxxabi/src/fallback_malloc.cpp

@@ -9,7 +9,7 @@
 #include "fallback_malloc.h"
 #include "abort_message.h"
 
-#include <__threading_support>
+#include <__thread/support.h>
 #ifndef _LIBCXXABI_HAS_NO_THREADS
 #if defined(__ELF__) && defined(_LIBCXXABI_LINK_PTHREAD_LIB)
 #pragma comment(lib, "pthread")

lib/libcxxabi/src/private_typeinfo.cpp

@@ -44,13 +44,25 @@
 #include <cstdint>
 #include <cassert>
 #include <string.h>
+#include "abort_message.h"
 
 #ifdef _LIBCXXABI_FORGIVING_DYNAMIC_CAST
-#include "abort_message.h"
 #include <sys/syslog.h>
 #include <atomic>
 #endif
 
+#if __has_feature(ptrauth_calls)
+#include <ptrauth.h>
+#endif
+
+template <typename T>
+static inline T* strip_vtable(T* vtable) {
+#if __has_feature(ptrauth_calls)
+  vtable = ptrauth_strip(vtable, ptrauth_key_cxx_vtable_pointer);
+#endif
+  return vtable;
+}
+
 static inline
 bool
 is_equal(const std::type_info* x, const std::type_info* y, bool use_strcmp)
@@ -102,10 +114,10 @@ void dyn_cast_get_derived_info(derived_object_info* info, const void* static_ptr
         reinterpret_cast<const uint8_t*>(vtable) + offset_to_ti_proxy;
     info->dynamic_type = *(reinterpret_cast<const __class_type_info* const*>(ptr_to_ti_proxy));
 #else
-    void **vtable = *static_cast<void ** const *>(static_ptr);
+  void** vtable = strip_vtable(*static_cast<void** const*>(static_ptr));
-    info->offset_to_derived = reinterpret_cast<ptrdiff_t>(vtable[-2]);
+  info->offset_to_derived = reinterpret_cast<ptrdiff_t>(vtable[-2]);
-    info->dynamic_ptr = static_cast<const char*>(static_ptr) + info->offset_to_derived;
+  info->dynamic_ptr = static_cast<const char*>(static_ptr) + info->offset_to_derived;
-    info->dynamic_type = static_cast<const __class_type_info*>(vtable[-1]);
+  info->dynamic_type = static_cast<const __class_type_info*>(vtable[-1]);
 #endif
 }
 
@@ -470,7 +482,7 @@ __class_type_info::can_catch(const __shim_type_info* thrown_type,
     if (thrown_class_type == 0)
         return false;
     // bullet 2
-    assert(adjustedPtr && "catching a class without an object?");
+    _LIBCXXABI_ASSERT(adjustedPtr, "catching a class without an object?");
     __dynamic_cast_info info = {thrown_class_type, 0, this, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, true, nullptr};
     info.number_of_dst_type = 1;
     thrown_class_type->has_unambiguous_public_base(&info, adjustedPtr, public_path);
@@ -560,7 +572,7 @@ __base_class_type_info::has_unambiguous_public_base(__dynamic_cast_info* info,
        find the layout.  */
     offset_to_base = __offset_flags >> __offset_shift;
     if (is_virtual) {
-      const char* vtable = *static_cast<const char* const*>(adjustedPtr);
+      const char* vtable = strip_vtable(*static_cast<const char* const*>(adjustedPtr));
       offset_to_base = update_offset_to_base(vtable, offset_to_base);
     }
   } else if (!is_virtual) {
@@ -1500,8 +1512,8 @@ __base_class_type_info::search_above_dst(__dynamic_cast_info* info,
     ptrdiff_t offset_to_base = __offset_flags >> __offset_shift;
     if (__offset_flags & __virtual_mask)
     {
-        const char* vtable = *static_cast<const char*const*>(current_ptr);
+      const char* vtable = strip_vtable(*static_cast<const char* const*>(current_ptr));
-        offset_to_base = update_offset_to_base(vtable, offset_to_base);
+      offset_to_base = update_offset_to_base(vtable, offset_to_base);
     }
     __base_type->search_above_dst(info, dst_ptr,
                                   static_cast<const char*>(current_ptr) + offset_to_base,
@@ -1520,8 +1532,8 @@ __base_class_type_info::search_below_dst(__dynamic_cast_info* info,
     ptrdiff_t offset_to_base = __offset_flags >> __offset_shift;
     if (__offset_flags & __virtual_mask)
     {
-        const char* vtable = *static_cast<const char*const*>(current_ptr);
+      const char* vtable = strip_vtable(*static_cast<const char* const*>(current_ptr));
-        offset_to_base = update_offset_to_base(vtable, offset_to_base);
+      offset_to_base = update_offset_to_base(vtable, offset_to_base);
     }
     __base_type->search_below_dst(info,
                                   static_cast<const char*>(current_ptr) + offset_to_base,