[clang] cb6c0f1 - [clang][Interp] Ignore ArrayDecay ops for null pointers

[Timm Bäder via cfe-commits]

Author: Timm Bäder
Date: 2024-02-28T16:16:03+01:00
New Revision: cb6c0f1d28c0d1915d1ca9a198254e3828af2384

URL: https://github.com/llvm/llvm-project/commit/cb6c0f1d28c0d1915d1ca9a198254e3828af2384
DIFF: https://github.com/llvm/llvm-project/commit/cb6c0f1d28c0d1915d1ca9a198254e3828af2384.diff

LOG: [clang][Interp] Ignore ArrayDecay ops for null pointers

Just don't do anything and let later operations handle the diagnostics.

Added: 
    

Modified: 
    clang/lib/AST/Interp/Interp.h
    clang/test/AST/Interp/cxx11.cpp

Removed: 
    


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diff  --git a/clang/lib/AST/Interp/Interp.h b/clang/lib/AST/Interp/Interp.h
index db52f6649c18ba..241d5941e143ee 100644
--- a/clang/lib/AST/Interp/Interp.h
+++ b/clang/lib/AST/Interp/Interp.h
@@ -1933,7 +1933,7 @@ inline bool ArrayElemPop(InterpState &S, CodePtr OpPC, uint32_t Index) {
 inline bool ArrayDecay(InterpState &S, CodePtr OpPC) {
   const Pointer &Ptr = S.Stk.pop<Pointer>();
 
-  if (Ptr.isDummy()) {
+  if (Ptr.isZero() || Ptr.isDummy()) {
     S.Stk.push<Pointer>(Ptr);
     return true;
   }

diff  --git a/clang/test/AST/Interp/cxx11.cpp b/clang/test/AST/Interp/cxx11.cpp
index 29098ea694c688..993e3618a37848 100644
--- a/clang/test/AST/Interp/cxx11.cpp
+++ b/clang/test/AST/Interp/cxx11.cpp
@@ -28,3 +28,5 @@ struct S {
 };
 constexpr S s = { 5 };
 constexpr const int *p = &s.m + 1;
+
+constexpr const int *np2 = &(*(int(*)[4])nullptr)[0]; // ok