[LifetimeAnalysis] Do not forbid void deref type in gsl::Pointer/gsl::Owner annotations
It turns out it is useful to be able to define the deref type as void.
In case we have a type erased owner, we want to express that the pointee
can be basically any type. It should not be unnatural to have a void
deref type as we already familiar with "pointers to void".
Differential Revision: https://reviews.llvm.org/D72097
diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
index 9b4afa8..515476d 100644
--- a/clang/include/clang/Basic/AttrDocs.td
+++ b/clang/include/clang/Basic/AttrDocs.td
@@ -4590,7 +4590,7 @@
The argument ``T`` is optional and is ignored.
This attribute may be used by analysis tools and has no effect on code
-generation.
+generation. A ``void`` argument means that the class can own any type.
See Pointer_ for an example.
}];
@@ -4616,7 +4616,7 @@
The argument ``T`` is optional and is ignored.
This attribute may be used by analysis tools and has no effect on code
-generation.
+generation. A ``void`` argument means that the pointer can point to any type.
Example:
When constructing an instance of a class annotated like this (a Pointer) from
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index a8f49fe..dd9649b 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2631,7 +2631,7 @@
def err_attributes_are_not_compatible : Error<
"%0 and %1 attributes are not compatible">;
def err_attribute_invalid_argument : Error<
- "%select{'void'|a reference type|an array type|a non-vector or "
+ "%select{a reference type|an array type|a non-vector or "
"non-vectorizable scalar type}0 is an invalid argument to attribute %1">;
def err_attribute_wrong_number_arguments : Error<
"%0 attribute %plural{0:takes no arguments|1:takes one argument|"
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 50951ad..02aebbe 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -2913,7 +2913,7 @@
if (!ParmType->isExtVectorType() && !ParmType->isFloatingType() &&
(ParmType->isBooleanType() ||
!ParmType->isIntegralType(S.getASTContext()))) {
- S.Diag(AL.getLoc(), diag::err_attribute_invalid_argument) << 3 << AL;
+ S.Diag(AL.getLoc(), diag::err_attribute_invalid_argument) << 2 << AL;
return;
}
@@ -4454,12 +4454,10 @@
ParmType = S.GetTypeFromParser(AL.getTypeArg(), &DerefTypeLoc);
unsigned SelectIdx = ~0U;
- if (ParmType->isVoidType())
+ if (ParmType->isReferenceType())
SelectIdx = 0;
- else if (ParmType->isReferenceType())
- SelectIdx = 1;
else if (ParmType->isArrayType())
- SelectIdx = 2;
+ SelectIdx = 1;
if (SelectIdx != ~0U) {
S.Diag(AL.getLoc(), diag::err_attribute_invalid_argument)
diff --git a/clang/test/SemaCXX/attr-gsl-owner-pointer.cpp b/clang/test/SemaCXX/attr-gsl-owner-pointer.cpp
index 5b43882..6c1bfe4 100644
--- a/clang/test/SemaCXX/attr-gsl-owner-pointer.cpp
+++ b/clang/test/SemaCXX/attr-gsl-owner-pointer.cpp
@@ -31,9 +31,11 @@
// CHECK: OwnerAttr {{.*}} int
class [[gsl::Owner(void)]] OwnerVoidDerefType{};
-// expected-error@-1 {{'void' is an invalid argument to attribute 'Owner'}}
+// CHECK: CXXRecordDecl {{.*}} OwnerVoidDerefType
+// CHECK: OwnerAttr {{.*}} void
class [[gsl::Pointer(void)]] PointerVoidDerefType{};
-// expected-error@-1 {{'void' is an invalid argument to attribute 'Pointer'}}
+// CHECK: CXXRecordDecl {{.*}} PointerVoidDerefType
+// CHECK: PointerAttr {{.*}} void
class [[gsl::Pointer(int)]] AddConflictLater{};
// CHECK: CXXRecordDecl {{.*}} AddConflictLater