[clang] [clang][bytecode] Ignore explicit calls to trivial dtors (PR #112841)

[Timm Baeder via cfe-commits]

https://github.com/tbaederr created https://github.com/llvm/llvm-project/pull/112841

This is what the current interpreter does as well.

>From 349cda342a9febd60419ea53ea34cdf8a7b2523f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timm=20B=C3=A4der?= <tbaeder at redhat.com>
Date: Fri, 18 Oct 2024 06:25:29 +0200
Subject: [PATCH] [clang][bytecode] Ignore explicit calls to trivial dtors

This is what the current interpreter does as well.
---
 clang/lib/AST/ByteCode/Compiler.cpp       |  4 ++++
 clang/test/AST/ByteCode/placement-new.cpp | 13 +++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp
index 8ca63bf64aa0ef..a71c0dcc9381e8 100644
--- a/clang/lib/AST/ByteCode/Compiler.cpp
+++ b/clang/lib/AST/ByteCode/Compiler.cpp
@@ -4535,6 +4535,10 @@ bool Compiler<Emitter>::VisitCallExpr(const CallExpr *E) {
       return VisitBuiltinCallExpr(E, Builtin::BI__builtin_operator_delete);
     }
   }
+  // Explicit calls to trivial destructors
+  if (const auto *DD = dyn_cast_if_present<CXXDestructorDecl>(FuncDecl);
+      DD && DD->isTrivial())
+    return true;
 
   QualType ReturnType = E->getCallReturnType(Ctx.getASTContext());
   std::optional<PrimType> T = classify(ReturnType);
diff --git a/clang/test/AST/ByteCode/placement-new.cpp b/clang/test/AST/ByteCode/placement-new.cpp
index 8e6d802e93295c..5673b5cba3f700 100644
--- a/clang/test/AST/ByteCode/placement-new.cpp
+++ b/clang/test/AST/ByteCode/placement-new.cpp
@@ -311,3 +311,16 @@ constexpr bool change_union_member() {
   return u.b == 2;
 }
 static_assert(change_union_member());
+
+namespace PR48606 {
+  struct A { mutable int n = 0; };
+
+  constexpr bool f() {
+    A a;
+    A *p = &a;
+    p->~A();
+    std::construct_at<A>(p);
+    return true;
+  }
+  static_assert(f());
+}