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[clang][ExprConst] Diagnose ptr subs with non-zero offset #135938

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Merged
merged 1 commit into from
Apr 17, 2025
Merged

[clang][ExprConst] Diagnose ptr subs with non-zero offset #135938

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3 changes: 0 additions & 3 deletions clang/lib/AST/ExprConstant.cpp
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Expand Up @@ -14764,9 +14764,6 @@ bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
// Reject differing bases from the normal codepath; we special-case
// comparisons to null.
if (!HasSameBase(LHSValue, RHSValue)) {
// Handle &&A - &&B.
if (!LHSValue.Offset.isZero() || !RHSValue.Offset.isZero())
return Error(E);
const Expr *LHSExpr = LHSValue.Base.dyn_cast<const Expr *>();
const Expr *RHSExpr = RHSValue.Base.dyn_cast<const Expr *>();

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2 changes: 1 addition & 1 deletion clang/test/AST/ByteCode/arrays.cpp
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Expand Up @@ -107,7 +107,7 @@ static_assert(k1 == 1, "");
static_assert((&arr[0] - &arr[1]) == -1, "");

constexpr int k2 = &arr2[1] - &arr[0]; // both-error {{must be initialized by a constant expression}} \
// expected-note {{arithmetic involving unrelated objects}}
// both-note {{arithmetic involving unrelated objects}}

static_assert((arr + 0) == arr, "");
static_assert(&arr[0] == arr, "");
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4 changes: 4 additions & 0 deletions clang/test/SemaCXX/constant-expression-cxx11.cpp
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Expand Up @@ -409,6 +409,10 @@ constexpr int a = 0;
constexpr int b = 1;
constexpr int n = &b - &a; // expected-error {{must be initialized by a constant expression}} \
// expected-note {{arithmetic involving unrelated objects '&b' and '&a' has unspecified value}}
constexpr static int arrk[2] = {1,2};
constexpr static int arrk2[2] = {3,4};
constexpr int k2 = &arrk[1] - &arrk2[0]; // expected-error {{must be initialized by a constant expression}} \
// expected-note {{arithmetic involving unrelated objects}}

namespace MaterializeTemporary {

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