https://github.com/AmrDeveloper created https://github.com/llvm/llvm-project/pull/166055
Report a diagnostic in case vector_size or ext_vector_type attributes are used with a negative size. The same evaluation result can be used for other checks, for example, the too big a size. Issue #165463 >From 8173191f053c4eb6d60c81a69682489fd50ff5d7 Mon Sep 17 00:00:00 2001 From: Amr Hesham <[email protected]> Date: Sun, 2 Nov 2025 12:00:40 +0100 Subject: [PATCH] [clang] Report Diagnostic when builtin vector has negative size --- clang/docs/ReleaseNotes.rst | 3 +++ .../clang/Basic/DiagnosticSemaKinds.td | 2 ++ clang/lib/Sema/SemaType.cpp | 24 ++++++++++++++++--- clang/test/SemaCXX/vector.cpp | 5 ++++ 4 files changed, 31 insertions(+), 3 deletions(-) diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 92fc9381a5868..f3a8367ad16e5 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -390,6 +390,9 @@ Improvements to Clang's diagnostics that were previously incorrectly accepted in case of other irrelevant conditions are now consistently diagnosed, identical to C++ mode. +- Clang now emits a diagnostic in case `vector_size` or `ext_vector_type` + attributes are used with a negative size (#GH165463). + Improvements to Clang's time-trace ---------------------------------- diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index 4e369be0bbb92..fa509536bf021 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -3510,6 +3510,8 @@ def err_init_method_bad_return_type : Error< "init methods must return an object pointer type, not %0">; def err_attribute_invalid_size : Error< "vector size not an integral multiple of component size">; +def err_attribute_vec_negative_size + : Error<"vector must have non-negative size">; def err_attribute_zero_size : Error<"zero %0 size">; def err_attribute_size_too_large : Error<"%0 size too large">; def err_typecheck_sve_rvv_ambiguous : Error< diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp index 280b3c92cce14..3345ed0dbbc0f 100644 --- a/clang/lib/Sema/SemaType.cpp +++ b/clang/lib/Sema/SemaType.cpp @@ -8285,10 +8285,20 @@ static void HandleVectorSizeAttr(QualType &CurType, const ParsedAttr &Attr, Expr *SizeExpr = Attr.getArgAsExpr(0); QualType T = S.BuildVectorType(CurType, SizeExpr, Attr.getLoc()); - if (!T.isNull()) - CurType = T; - else + if (T.isNull()) { + Attr.setInvalid(); + return; + } + + std::optional<llvm::APSInt> VecSize = + SizeExpr->getIntegerConstantExpr(S.Context); + if (VecSize && VecSize->isNegative()) { + S.Diag(SizeExpr->getExprLoc(), diag::err_attribute_vec_negative_size); Attr.setInvalid(); + return; + } + + CurType = T; } /// Process the OpenCL-like ext_vector_type attribute when it occurs on @@ -8306,6 +8316,14 @@ static void HandleExtVectorTypeAttr(QualType &CurType, const ParsedAttr &Attr, QualType T = S.BuildExtVectorType(CurType, SizeExpr, Attr.getLoc()); if (!T.isNull()) CurType = T; + + std::optional<llvm::APSInt> VecSize = + SizeExpr->getIntegerConstantExpr(S.Context); + if (VecSize && VecSize->isNegative()) { + S.Diag(SizeExpr->getExprLoc(), diag::err_attribute_vec_negative_size); + Attr.setInvalid(); + return; + } } static bool isPermittedNeonBaseType(QualType &Ty, VectorKind VecKind, Sema &S) { diff --git a/clang/test/SemaCXX/vector.cpp b/clang/test/SemaCXX/vector.cpp index 808bdb679b09c..eea0b4756fae3 100644 --- a/clang/test/SemaCXX/vector.cpp +++ b/clang/test/SemaCXX/vector.cpp @@ -786,3 +786,8 @@ const long long e = *0; // expected-error {{indirection requires pointer operand double f = a - e; // expected-error {{cannot initialize a variable of type 'double' with an rvalue of type '__attribute__((__vector_size__(1 * sizeof(double)))) double' (vector of 1 'double' value)}} int h = c - e; // expected-error {{cannot initialize a variable of type 'int' with an rvalue of type '__attribute__((__vector_size__(1 * sizeof(long)))) long' (vector of 1 'long' value)}} } + +typedef int v_neg_size __attribute__((vector_size(-8))); // expected-error{{vector must have non-negative size}} +typedef int v_neg_size_2 __attribute__((vector_size(-1 * 8))); // expected-error{{vector must have non-negative size}} +typedef int v_ext_neg_size __attribute__((ext_vector_type(-8))); // expected-error{{vector must have non-negative size}} +typedef int v_ext_neg_size2 __attribute__((ext_vector_type(-1 * 8))); // expected-error{{vector must have non-negative size}} _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
