[PATCH] D75573: [Sema][SVE] Reject aligned/_Alignas for sizeless types

[Richard Sandiford via Phabricator via cfe-commits]

This revision was automatically updated to reflect the committed changes.
Closed by commit rG627b5c12068c: [Sema][SVE] Reject aligned/_Alignas for sizeless types (authored by rsandifo-arm).

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D75573/new/

https://reviews.llvm.org/D75573

Files:
  clang/include/clang/Basic/DiagnosticSemaKinds.td
  clang/lib/Sema/SemaDeclAttr.cpp
  clang/test/Sema/sizeless-1.c
  clang/test/SemaCXX/sizeless-1.cpp


Index: clang/test/SemaCXX/sizeless-1.cpp
===================================================================
--- clang/test/SemaCXX/sizeless-1.cpp
+++ clang/test/SemaCXX/sizeless-1.cpp
@@ -61,6 +61,10 @@
   svint8_t local_int8;
   svint16_t local_int16;
 
+  svint8_t __attribute__((aligned)) aligned_int8_1;    // expected-error {{'aligned' attribute cannot be applied to sizeless type 'svint8_t'}}
+  svint8_t __attribute__((aligned(4))) aligned_int8_2; // expected-error {{'aligned' attribute cannot be applied to sizeless type 'svint8_t'}}
+  svint8_t _Alignas(int) aligned_int8_3;               // expected-error {{'_Alignas' attribute cannot be applied to sizeless type 'svint8_t'}}
+
   int _Alignas(svint8_t) aligned_int; // expected-error {{invalid application of 'alignof' to sizeless type 'svint8_t'}}
 
   // Using pointers to sizeless data isn't wrong here, but because the
Index: clang/test/Sema/sizeless-1.c
===================================================================
--- clang/test/Sema/sizeless-1.c
+++ clang/test/Sema/sizeless-1.c
@@ -51,6 +51,10 @@
   svint8_t local_int8;
   svint16_t local_int16;
 
+  svint8_t __attribute__((aligned)) aligned_int8_1;    // expected-error {{'aligned' attribute cannot be applied to sizeless type 'svint8_t'}}
+  svint8_t __attribute__((aligned(4))) aligned_int8_2; // expected-error {{'aligned' attribute cannot be applied to sizeless type 'svint8_t'}}
+  svint8_t _Alignas(int) aligned_int8_3;               // expected-error {{'_Alignas' attribute cannot be applied to sizeless type 'svint8_t'}}
+
   int _Alignas(svint8_t) aligned_int; // expected-error {{invalid application of 'alignof' to sizeless type 'svint8_t'}}
 
   // Using pointers to sizeless data isn't wrong here, but because the
Index: clang/lib/Sema/SemaDeclAttr.cpp
===================================================================
--- clang/lib/Sema/SemaDeclAttr.cpp
+++ clang/lib/Sema/SemaDeclAttr.cpp
@@ -3868,6 +3868,7 @@
   //   not specify an alignment that is less strict than the alignment that
   //   would otherwise be required for the entity being declared.
   AlignedAttr *AlignasAttr = nullptr;
+  AlignedAttr *LastAlignedAttr = nullptr;
   unsigned Align = 0;
   for (auto *I : D->specific_attrs<AlignedAttr>()) {
     if (I->isAlignmentDependent())
@@ -3875,9 +3876,13 @@
     if (I->isAlignas())
       AlignasAttr = I;
     Align = std::max(Align, I->getAlignment(Context));
+    LastAlignedAttr = I;
   }
 
-  if (AlignasAttr && Align) {
+  if (Align && DiagTy->isSizelessType()) {
+    Diag(LastAlignedAttr->getLocation(), diag::err_attribute_sizeless_type)
+        << LastAlignedAttr << DiagTy;
+  } else if (AlignasAttr && Align) {
     CharUnits RequestedAlign = Context.toCharUnitsFromBits(Align);
     CharUnits NaturalAlign = Context.getTypeAlignInChars(UnderlyingTy);
     if (NaturalAlign > RequestedAlign)
Index: clang/include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2807,6 +2807,8 @@
   "redeclaration has different alignment requirement (%1 vs %0)">;
 def err_alignas_underaligned : Error<
   "requested alignment is less than minimum alignment of %1 for type %0">;
+def err_attribute_sizeless_type : Error<
+  "%0 attribute cannot be applied to sizeless type %1">;
 def err_attribute_argument_n_type : Error<
   "%0 attribute requires parameter %1 to be %select{int or bool|an integer "
   "constant|a string|an identifier}2">;


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D75573.249984.patch
Type: text/x-patch
Size: 3568 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20200312/2472df91/attachment-0001.bin>