diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -188,10 +188,11 @@
   and `DR1734 <https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#1734>`_.
 - Class member variables are now in scope when parsing a ``requires`` clause. Fixes
   `GH55216 <https://github.com/llvm/llvm-project/issues/55216>`_.
-
 - Correctly set expression evaluation context as 'immediate function context' in
   consteval functions.
   This fixes `GH51182 <https://github.com/llvm/llvm-project/issues/51182>`
+- Fixes an assert crash caused by looking up missing vtable information on ``consteval``
+  virtual functions. Fixes `GH55065 <https://github.com/llvm/llvm-project/issues/55065>`_.
 
 
 C++2b Feature Support
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -26,6 +26,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/AST/RecordLayout.h"
 #include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/AST/VTableBuilder.h"
 #include "clang/Basic/CodeGenOptions.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Basic/SourceManager.h"
@@ -1758,7 +1759,7 @@
   llvm::DISubprogram::DISPFlags SPFlags = llvm::DISubprogram::SPFlagZero;
   int ThisAdjustment = 0;
 
-  if (Method->isVirtual()) {
+  if (VTableContextBase::hasVtableSlot(Method)) {
     if (Method->isPure())
       SPFlags |= llvm::DISubprogram::SPFlagPureVirtual;
     else
diff --git a/clang/test/CodeGenCXX/cxx20-consteval-crash.cpp b/clang/test/CodeGenCXX/cxx20-consteval-crash.cpp
--- a/clang/test/CodeGenCXX/cxx20-consteval-crash.cpp
+++ b/clang/test/CodeGenCXX/cxx20-consteval-crash.cpp
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 -no-opaque-pointers -triple x86_64-unknown-linux-gnu -std=c++20 %s -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 -emit-obj -debug-info-kind=constructor -std=c++20 %s -o -
 
 namespace PR50787 {
 // This code would previously cause a crash.
@@ -71,3 +72,23 @@
   return function(Item{'a'}, Item{'a'});
 }
 } // namespace Issue58871
+
+namespace Issue55065 {
+struct Base {
+  consteval virtual int Get() const = 0;
+};
+
+struct Derived : Base {
+  consteval int Get() const override {
+    return 42;
+  }
+};
+
+int foo() {
+  constexpr Derived a;
+
+  auto val = a.Get();
+  return val;
+}
+} // namespace Issue55065
+