[clang] 2725e2c - [clang][Interp] Fix ImplicitValueInitExprs for pointer types

[Timm Bäder via cfe-commits]

Author: Timm Bäder
Date: 2023-01-25T12:31:49+01:00
New Revision: 2725e2c0323f1408467452e3cc2a4a8cb3ea49a7

URL: https://github.com/llvm/llvm-project/commit/2725e2c0323f1408467452e3cc2a4a8cb3ea49a7
DIFF: https://github.com/llvm/llvm-project/commit/2725e2c0323f1408467452e3cc2a4a8cb3ea49a7.diff

LOG: [clang][Interp] Fix ImplicitValueInitExprs for pointer types

This previously ran into an "unknown type" assertion when trying to emit
a 'Zero' op for a pointer type. Emit a NullPtr op instead.

Differential Revision: https://reviews.llvm.org/D137235

Added: 
    

Modified: 
    clang/lib/AST/Interp/ByteCodeExprGen.cpp
    clang/test/AST/Interp/literals.cpp

Removed: 
    


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diff  --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
index dd7d88ae715d..5952e3aa681c 100644
--- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
@@ -279,10 +279,15 @@ bool ByteCodeExprGen<Emitter>::VisitPointerArithBinOp(const BinaryOperator *E) {
 
 template <class Emitter>
 bool ByteCodeExprGen<Emitter>::VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
-  if (std::optional<PrimType> T = classify(E))
-    return this->emitZero(*T, E);
+  std::optional<PrimType> T = classify(E);
 
-  return false;
+  if (!T)
+    return false;
+
+  if (E->getType()->isPointerType())
+    return this->emitNullPtr(E);
+
+  return this->emitZero(*T, E);
 }
 
 template <class Emitter>

diff  --git a/clang/test/AST/Interp/literals.cpp b/clang/test/AST/Interp/literals.cpp
index 4fc9489941e5..4c88e861a443 100644
--- a/clang/test/AST/Interp/literals.cpp
+++ b/clang/test/AST/Interp/literals.cpp
@@ -49,7 +49,10 @@ namespace IntegralCasts {
   static_assert(!nu, "");
 };
 
-
+constexpr int UninitI; // expected-error {{must be initialized by a constant expression}} \
+                       // ref-error {{must be initialized by a constant expression}}
+constexpr int *UninitPtr; // expected-error {{must be initialized by a constant expression}} \
+                          // ref-error {{must be initialized by a constant expression}}
 
 constexpr bool getTrue() { return true; }
 constexpr bool getFalse() { return false; }