[clang] [clang][bytecode] Diagnose weak reads in final load (PR #109515)

[Timm Baeder via cfe-commits]

https://github.com/tbaederr created https://github.com/llvm/llvm-project/pull/109515

They aren't allowed here either.

>From bc5bbba9c0ab2aa19172d45b2fad628ec531bb8d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timm=20B=C3=A4der?= <tbaeder at redhat.com>
Date: Sat, 21 Sep 2024 08:28:52 +0200
Subject: [PATCH] [clang][bytecode] Diagnose weak reads in final load

They aren't allowed here either.
---
 clang/lib/AST/ByteCode/Interp.cpp   | 2 ++
 clang/test/CodeGenCXX/weak-init.cpp | 1 +
 2 files changed, 3 insertions(+)

diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp
index 17cf3ccdeb6a94..65b4c0a9cb7660 100644
--- a/clang/lib/AST/ByteCode/Interp.cpp
+++ b/clang/lib/AST/ByteCode/Interp.cpp
@@ -620,6 +620,8 @@ bool CheckFinalLoad(InterpState &S, CodePtr OpPC, const Pointer &Ptr) {
     return false;
   if (!CheckTemporary(S, OpPC, Ptr, AK_Read))
     return false;
+  if (!CheckWeak(S, OpPC, Ptr))
+    return false;
   if (!CheckMutable(S, OpPC, Ptr))
     return false;
   return true;
diff --git a/clang/test/CodeGenCXX/weak-init.cpp b/clang/test/CodeGenCXX/weak-init.cpp
index 634021f38f854c..d9b17d9ca74f87 100644
--- a/clang/test/CodeGenCXX/weak-init.cpp
+++ b/clang/test/CodeGenCXX/weak-init.cpp
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -emit-llvm %s -o - -fexperimental-new-constant-interpreter | FileCheck %s
 
 extern const int W __attribute__((weak)) = 99;
 const int S = 77;