[clang] [Clang] Fix null pointer dereference in enum debug info generation (PR #97105)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-clang

@llvm/pr-subscribers-clang-codegen

Author: None (smanna12)

<details>
<summary>Changes</summary>

This patch prevents dereferencing a null enum definition by returning `nullptr` if `getDefinition()` fails in `CreateTypeDefinition()`.

---
Full diff: https://github.com/llvm/llvm-project/pull/97105.diff


1 Files Affected:

- (modified) clang/lib/CodeGen/CGDebugInfo.cpp (+4) 


``````````diff
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 3d8a715b692de..c236e2657fe98 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -3518,6 +3518,10 @@ llvm::DIType *CGDebugInfo::CreateTypeDefinition(const EnumType *Ty) {
 
   SmallVector<llvm::Metadata *, 16> Enumerators;
   ED = ED->getDefinition();
+
+  if (!ED)
+    return nullptr;
+
   for (const auto *Enum : ED->enumerators()) {
     Enumerators.push_back(
         DBuilder.createEnumerator(Enum->getName(), Enum->getInitVal()));

``````````

</details>


https://github.com/llvm/llvm-project/pull/97105