[clang] e44784f - [clang][bytecode] Fix pseudo dtor calls on non-pointers (#153970)

[via cfe-commits]

Author: Timm Baeder
Date: 2025-08-17T08:47:57+02:00
New Revision: e44784fb44bd00acc0ecd25537a359c3a1df8f17

URL: https://github.com/llvm/llvm-project/commit/e44784fb44bd00acc0ecd25537a359c3a1df8f17
DIFF: https://github.com/llvm/llvm-project/commit/e44784fb44bd00acc0ecd25537a359c3a1df8f17.diff

LOG: [clang][bytecode] Fix pseudo dtor calls on non-pointers (#153970)

The isGLValue() check made us ignore expressions we shouldn't ignore.

Added: 
    

Modified: 
    clang/lib/AST/ByteCode/Compiler.cpp
    clang/test/AST/ByteCode/builtin-functions.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp
index 6c6c8d41d3b93..b228cea7cb58b 100644
--- a/clang/lib/AST/ByteCode/Compiler.cpp
+++ b/clang/lib/AST/ByteCode/Compiler.cpp
@@ -5146,7 +5146,8 @@ bool Compiler<Emitter>::VisitCallExpr(const CallExpr *E) {
     if (!this->emitCheckPseudoDtor(E))
       return false;
     const Expr *Base = PD->getBase();
-    if (!Base->isGLValue())
+    // E.g. `using T = int; 0.~T();`.
+    if (OptPrimType BaseT = classify(Base); !BaseT || BaseT != PT_Ptr)
       return this->discard(Base);
     if (!this->visit(Base))
       return false;

diff  --git a/clang/test/AST/ByteCode/builtin-functions.cpp b/clang/test/AST/ByteCode/builtin-functions.cpp
index 1223cf8bdc74f..878c0d1a40f26 100644
--- a/clang/test/AST/ByteCode/builtin-functions.cpp
+++ b/clang/test/AST/ByteCode/builtin-functions.cpp
@@ -21,6 +21,27 @@
 #error "huh?"
 #endif
 
+
+inline constexpr void* operator new(__SIZE_TYPE__, void* p) noexcept { return p; }
+namespace std {
+  using size_t = decltype(sizeof(0));
+  template<typename T> struct allocator {
+    constexpr T *allocate(size_t N) {
+      return (T*)__builtin_operator_new(sizeof(T) * N); // #alloc
+    }
+    constexpr void deallocate(void *p, __SIZE_TYPE__) {
+      __builtin_operator_delete(p);
+    }
+  };
+template<typename T, typename... Args>
+constexpr T* construct_at(T* p, Args&&... args) { return ::new((void*)p) T(static_cast<Args&&>(args)...); }
+
+  template<typename T>
+  constexpr void destroy_at(T* p) {
+    p->~T();
+  }
+}
+
 extern "C" {
   typedef decltype(sizeof(int)) size_t;
   extern size_t wcslen(const wchar_t *p);
@@ -1767,6 +1788,28 @@ namespace WithinLifetime {
     }
   } xstd; // both-error {{is not a constant expression}} \
           // both-note {{in call to}}
+
+  consteval bool test_dynamic(bool read_after_deallocate) {
+    std::allocator<int> a;
+    int* p = a.allocate(1);
+    // a.allocate starts the lifetime of an array,
+    // the complete object of *p has started its lifetime
+    if (__builtin_is_within_lifetime(p))
+      return false;
+    std::construct_at(p);
+    if (!__builtin_is_within_lifetime(p))
+      return false;
+    std::destroy_at(p);
+    if (__builtin_is_within_lifetime(p))
+      return false;
+    a.deallocate(p, 1);
+    if (read_after_deallocate)
+      __builtin_is_within_lifetime(p); // both-note {{read of heap allocated object that has been deleted}}
+    return true;
+  }
+  static_assert(test_dynamic(false));
+  static_assert(test_dynamic(true)); // both-error {{not an integral constant expression}} \
+                                     // both-note {{in call to}}
 }
 
 #ifdef __SIZEOF_INT128__