diff --git a/clang-tools-extra/clangd/unittests/HoverTests.cpp b/clang-tools-extra/clangd/unittests/HoverTests.cpp
--- a/clang-tools-extra/clangd/unittests/HoverTests.cpp
+++ b/clang-tools-extra/clangd/unittests/HoverTests.cpp
@@ -2963,6 +2963,20 @@
   EXPECT_EQ(HI->Documentation, "Foo bar baz");
 }
 
+TEST(Hover, ForwardStructNoCrash) {
+  Annotations T(R"cpp(
+  struct Foo;
+  int bar;
+  auto baz = (Fo^o*)&bar;
+    )cpp");
+
+  TestTU TU = TestTU::withCode(T.code());
+  auto AST = TU.build();
+  auto HI = getHover(AST, T.point(), format::getLLVMStyle(), nullptr);
+  ASSERT_TRUE(HI);
+  EXPECT_EQ(*HI->Value, "&bar");
+}
+
 } // namespace
 } // namespace clangd
 } // namespace clang
diff --git a/clang/lib/AST/APValue.cpp b/clang/lib/AST/APValue.cpp
--- a/clang/lib/AST/APValue.cpp
+++ b/clang/lib/AST/APValue.cpp
@@ -700,7 +700,9 @@
     if (!hasLValuePath()) {
       // No lvalue path: just print the offset.
       CharUnits O = getLValueOffset();
-      CharUnits S = Ctx ? Ctx->getTypeSizeInChars(InnerTy) : CharUnits::Zero();
+      CharUnits S = Ctx ? Ctx->getTypeSizeInCharsIfKnown(InnerTy).getValueOr(
+                              CharUnits::Zero())
+                        : CharUnits::Zero();
       if (!O.isZero()) {
         if (IsReference)
           Out << "*(";