[clang] 9d6e0dd - [clang][bytecode] Fix division by zero in CXXNewExpr handling (#205800)

[via cfe-commits]

Author: Timm Baeder
Date: 2026-06-26T09:16:18+02:00
New Revision: 9d6e0dd15a5f9aa975ffaa45da183c6c05cb8a03

URL: https://github.com/llvm/llvm-project/commit/9d6e0dd15a5f9aa975ffaa45da183c6c05cb8a03
DIFF: https://github.com/llvm/llvm-project/commit/9d6e0dd15a5f9aa975ffaa45da183c6c05cb8a03.diff

LOG: [clang][bytecode] Fix division by zero in CXXNewExpr handling (#205800)

Added: 
    

Modified: 
    clang/lib/AST/ByteCode/InterpHelpers.h
    clang/test/AST/ByteCode/new-delete.cpp

Removed: 
    


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diff  --git a/clang/lib/AST/ByteCode/InterpHelpers.h b/clang/lib/AST/ByteCode/InterpHelpers.h
index da305dcb565d5..4d908d1e44546 100644
--- a/clang/lib/AST/ByteCode/InterpHelpers.h
+++ b/clang/lib/AST/ByteCode/InterpHelpers.h
@@ -118,6 +118,10 @@ inline bool Invalid(InterpState &S, CodePtr OpPC) {
 template <typename SizeT>
 bool CheckArraySize(InterpState &S, CodePtr OpPC, SizeT *NumElements,
                     unsigned ElemSize, bool IsNoThrow) {
+
+  if (ElemSize == 0)
+    return true;
+
   // FIXME: Both the SizeT::from() as well as the
   // NumElements.toAPSInt() in this function are rather expensive.
 

diff  --git a/clang/test/AST/ByteCode/new-delete.cpp b/clang/test/AST/ByteCode/new-delete.cpp
index 0e2db787ca48c..b9c1e089e6536 100644
--- a/clang/test/AST/ByteCode/new-delete.cpp
+++ b/clang/test/AST/ByteCode/new-delete.cpp
@@ -1278,6 +1278,17 @@ namespace NonPrimitiveImplicitValueInitExpr {
   static_assert(m() == 0);
 }
 
+namespace ZeroSizeElems {
+  typedef int U[0];
+
+  constexpr bool foo() {
+    auto p = new U[3.14]; // both-warning {{implicit conversion}}
+    delete[] p;
+    return true;
+  }
+  static_assert(foo());
+}
+
 #else
 /// Make sure we reject this prior to C++20
 constexpr int a() { // both-error {{never produces a constant expression}}