[clang] [clang][bytecode] Fix contains check using llvm::find (PR #149050)

[Timm Baeder via cfe-commits]

https://github.com/tbaederr created https://github.com/llvm/llvm-project/pull/149050

We need to compare to the end() interator.

>From 361077f6389b7764f1b9ea3084a6caeb51d4cd52 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timm=20B=C3=A4der?= <tbaeder at redhat.com>
Date: Wed, 16 Jul 2025 11:40:07 +0200
Subject: [PATCH] [clang][bytecode] Fix contains check using llvm::find

We need to compare to the end() interator.
---
 clang/lib/AST/ByteCode/Interp.cpp                    | 3 ++-
 clang/test/AST/ByteCode/placement-new.cpp            | 8 ++++++++
 clang/test/SemaCXX/cxx2c-constexpr-placement-new.cpp | 1 +
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp
index 457de2bed37d6..bb9053164930b 100644
--- a/clang/lib/AST/ByteCode/Interp.cpp
+++ b/clang/lib/AST/ByteCode/Interp.cpp
@@ -575,7 +575,8 @@ bool CheckConst(InterpState &S, CodePtr OpPC, const Pointer &Ptr) {
 
   // The This pointer is writable in constructors and destructors,
   // even if isConst() returns true.
-  if (llvm::find(S.InitializingBlocks, Ptr.block()))
+  if (llvm::find(S.InitializingBlocks, Ptr.block()) !=
+      S.InitializingBlocks.end())
     return true;
 
   const QualType Ty = Ptr.getType();
diff --git a/clang/test/AST/ByteCode/placement-new.cpp b/clang/test/AST/ByteCode/placement-new.cpp
index 670def2d5870e..b587cd6eaf89c 100644
--- a/clang/test/AST/ByteCode/placement-new.cpp
+++ b/clang/test/AST/ByteCode/placement-new.cpp
@@ -486,3 +486,11 @@ namespace bitcast {
   }
   static_assert(foo() == 0);
 }
+
+constexpr int modify_const_variable() {
+  const int a = 10;
+  new ((int *)&a) int(12); // both-note {{modification of object of const-qualified type 'const int' is not allowed in a constant expression}}
+  return a;
+}
+static_assert(modify_const_variable()); // both-error {{not an integral constant expression}} \
+                                        // both-note {{in call to}}
diff --git a/clang/test/SemaCXX/cxx2c-constexpr-placement-new.cpp b/clang/test/SemaCXX/cxx2c-constexpr-placement-new.cpp
index 6f6f9b04aa392..4cf0e9ffe1d64 100644
--- a/clang/test/SemaCXX/cxx2c-constexpr-placement-new.cpp
+++ b/clang/test/SemaCXX/cxx2c-constexpr-placement-new.cpp
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 -std=c++2c -verify %s
+// RUN: %clang_cc1 -std=c++2c -verify %s -fexperimental-new-constant-interpreter
 
 
 namespace std {