[clang] Non-object types are non-trivially relocatable

[AMP999]

Both active C++ proposals (P1144 and P2786) agree that is_trivially_relocatable_v<int&> and is_trivially_relocatable_v<int()> should be false, not true. Only complete object types can be trivially relocatable.

Fixes #67498

[llvmbot]

@llvm/pr-subscribers-clang

Author: Amirreza Ashouri (AMP999)

Changes

Both active C++ proposals (P1144 and P2786) agree that is_trivially_relocatable_v<int&> and is_trivially_relocatable_v<int()> should be false, not true. Only complete object types can be trivially relocatable.

Fixes #67498

---

Full diff: https://github.com/llvm/llvm-project/pull/69734.diff

1 Files Affected:

• (modified) clang/lib/AST/Type.cpp (+2)

diff --git a/clang/lib/AST/Type.cpp b/clang/lib/AST/Type.cpp
index 8389b1423058197..bdeff1e4ac5b604 100644
--- a/clang/lib/AST/Type.cpp
+++ b/clang/lib/AST/Type.cpp
@@ -2649,6 +2649,8 @@ bool QualType::isTriviallyRelocatableType(const ASTContext &Context) const {
 
   if (BaseElementType->isIncompleteType()) {
     return false;
+  } else if (!BaseElementType->isObjectType()) {
+    return false;
   } else if (const auto *RD = BaseElementType->getAsRecordDecl()) {
     return RD->canPassInRegisters();
   } else {

[cor3ntin]

Can you add tests / release notes? (the change itself looks fine to me)

[AMP999]

@cor3ntin Are these tests what you had in mind? Are they sufficient? What else should I add?

[AMP999]

@cor3ntin Gentle ping!

[cor3ntin]

@AMP999 Sorry, I'm in a committee meeting this week. tests look good. it's still missing a release note though

[AMP999]

Thank you! No problem! I'll add the release notes.

[cor3ntin]

LGTM, thanks!

[AMP999]

LGTM, thanks!

You're welcome!

[AMP999]

@cor3ntin Could you land this for me, please?

[cor3ntin]

@AMP999 can you resolve the conflict?

[AMP999]

Oh, Sure. I didn't notice that.

[AMP999]

@cor3ntin I've fixed that.