2019-11-01 Nathan Sidwell <nathan@acm.org>
cp/
* class.c (check_field_decls): Refactor.
testsuite/
* g++.dg/template/fn.C: New.
===================================================================
@@ -3449,8 +3449,5 @@ check_field_decl (tree field,
All of these flags should be initialized before calling this
- function.
-
- Returns a pointer to the end of the TYPE_FIELDs chain; additional
- fields can be added by adding to this chain. */
+ function. */
static void
@@ -3459,102 +3456,99 @@ check_field_decls (tree t, tree *access_
int *no_const_asn_ref_p)
{
- tree *field;
- tree *next;
int cant_pack = 0;
- int field_access = -1;
/* Assume there are no access declarations. */
*access_decls = NULL_TREE;
- /* Assume this class has no pointer members. */
- bool has_pointers = false;
- /* Assume none of the members of this class have default
- initializations. */
- bool any_default_members = false;
- /* Assume none of the non-static data members are of non-volatile literal
- type. */
+ /* Effective C has things to say about classes with pointer members. */
+ tree pointer_member = NULL_TREE;
+ /* Default initialized members affect the whole class. */
+ tree default_init_member = NULL_TREE;
+ /* Lack of any non-static data member of non-volatile literal
+ type affects a union. */
bool found_nv_literal_p = false;
+ /* Standard layout requires all FIELDS have same access. */
+ int field_access = -1;
- for (field = &TYPE_FIELDS (t); *field; field = next)
+ for (tree field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
{
- tree x = *field;
- tree type = TREE_TYPE (x);
- int this_field_access;
+ tree type = TREE_TYPE (field);
- next = &DECL_CHAIN (x);
-
- if (TREE_CODE (x) == USING_DECL)
+ switch (TREE_CODE (field))
{
- /* Save the access declarations for our caller. */
- *access_decls = tree_cons (NULL_TREE, x, *access_decls);
- continue;
- }
-
- if (TREE_CODE (x) == TYPE_DECL
- || TREE_CODE (x) == TEMPLATE_DECL)
- continue;
-
- if (TREE_CODE (x) == FUNCTION_DECL)
- /* FIXME: We should fold in the checking from check_methods. */
- continue;
+ default:
+ gcc_unreachable ();
- /* If we've gotten this far, it's a data member, possibly static,
- or an enumerator. */
- if (TREE_CODE (x) != CONST_DECL)
- DECL_CONTEXT (x) = t;
+ case USING_DECL:
+ /* Save the access declarations for our caller. */
+ *access_decls = tree_cons (NULL_TREE, field, *access_decls);
+ break;
- /* When this goes into scope, it will be a non-local reference. */
- DECL_NONLOCAL (x) = 1;
+ case TYPE_DECL:
+ case TEMPLATE_DECL:
+ break;
+
+ case FUNCTION_DECL:
+ /* FIXME: We should fold in the checking from check_methods. */
+ break;
+
+ case CONST_DECL:
+ DECL_NONLOCAL (field) = 1;
+ break;
+
+ case VAR_DECL:
+ if (TREE_CODE (t) == UNION_TYPE
+ && cxx_dialect < cxx11)
+ {
+ /* [class.union]
- if (TREE_CODE (t) == UNION_TYPE)
- {
- /* [class.union] (C++98)
+ (C++98) If a union contains a static data member,
+ ... the program is ill-formed. */
+ if (cxx_dialect < cxx11)
+ error ("in C++98 %q+D may not be static because it is "
+ "a member of a union", field);
+ }
+ goto data_member;
+
+ case FIELD_DECL:
+ if (TREE_CODE (t) == UNION_TYPE)
+ {
+ /* [class.union]
- If a union contains a static data member, or a member of
- reference type, the program is ill-formed.
+ If a union contains ... or a [non-static data] member
+ of reference type, the program is ill-formed. */
+ if (TYPE_REF_P (type))
+ error ("non-static data member %q+D in a union may not "
+ "have reference type %qT", field, type);
+ }
- In C++11 [class.union] says:
- If a union contains a non-static data member of reference type
- the program is ill-formed. */
- if (VAR_P (x) && cxx_dialect < cxx11)
+ data_member:
+ /* Common VAR_DECL & FIELD_DECL processing. */
+ DECL_CONTEXT (field) = t;
+ DECL_NONLOCAL (field) = 1;
+
+ /* Template instantiation can cause this. Perhaps this
+ should be a specific instantiation check? */
+ if (TREE_CODE (type) == FUNCTION_TYPE)
{
- error ("in C++98 %q+D may not be static because it is "
- "a member of a union", x);
- continue;
+ error ("data member %q+D invalidly declared function type", field);
+ type = build_pointer_type (type);
+ TREE_TYPE (field) = type;
}
- if (TYPE_REF_P (type)
- && TREE_CODE (x) == FIELD_DECL)
+ else if (TREE_CODE (type) == METHOD_TYPE)
{
- error ("non-static data member %q+D in a union may not "
- "have reference type %qT", x, type);
- continue;
+ error ("data member %q+D invalidly declared method type", field);
+ type = build_pointer_type (type);
+ TREE_TYPE (field) = type;
}
- }
- /* Perform error checking that did not get done in
- grokdeclarator. */
- if (TREE_CODE (type) == FUNCTION_TYPE)
- {
- error ("field %q+D invalidly declared function type", x);
- type = build_pointer_type (type);
- TREE_TYPE (x) = type;
- }
- else if (TREE_CODE (type) == METHOD_TYPE)
- {
- error ("field %q+D invalidly declared method type", x);
- type = build_pointer_type (type);
- TREE_TYPE (x) = type;
+ break;
}
- if (type == error_mark_node)
+ if (TREE_CODE (field) != FIELD_DECL)
continue;
- if (TREE_CODE (x) == CONST_DECL || VAR_P (x))
+ if (type == error_mark_node)
continue;
- /* Now it can only be a FIELD_DECL. */
-
- if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
- CLASSTYPE_NON_AGGREGATE (t) = 1;
-
/* If it is not a union and at least one non-static data member is
non-literal, the whole class becomes non-literal. Per Core/1453,
@@ -3571,13 +3565,21 @@ check_field_decls (tree t, tree *access_
}
- /* A standard-layout class is a class that:
- ...
- has the same access control (Clause 11) for all non-static data members,
- ... */
- this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
- if (field_access == -1)
- field_access = this_field_access;
- else if (this_field_access != field_access)
- CLASSTYPE_NON_STD_LAYOUT (t) = 1;
+ int this_field_access = (TREE_PROTECTED (field) ? 1
+ : TREE_PRIVATE (field) ? 2 : 0);
+ if (field_access != this_field_access)
+ {
+ /* A standard-layout class is a class that:
+
+ ... has the same access control (Clause 11) for all
+ non-static data members, */
+ if (field_access < 0)
+ field_access = this_field_access;
+ else
+ CLASSTYPE_NON_STD_LAYOUT (t) = 1;
+
+ /* Aggregates must be public. */
+ if (this_field_access)
+ CLASSTYPE_NON_AGGREGATE (t) = 1;
+ }
/* If this is of reference type, check if it needs an init. */
@@ -3586,5 +3588,5 @@ check_field_decls (tree t, tree *access_
CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
CLASSTYPE_NON_STD_LAYOUT (t) = 1;
- if (DECL_INITIAL (x) == NULL_TREE)
+ if (DECL_INITIAL (field) == NULL_TREE)
SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
if (cxx_dialect < cxx11)
@@ -3605,25 +3607,22 @@ check_field_decls (tree t, tree *access_
if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
{
- warning_at
- (DECL_SOURCE_LOCATION (x), 0,
- "ignoring packed attribute because of unpacked non-POD field %q#D",
- x);
+ warning_at (DECL_SOURCE_LOCATION (field), 0,
+ "ignoring packed attribute because of"
+ " unpacked non-POD field %q#D", field);
cant_pack = 1;
}
- else if (DECL_C_BIT_FIELD (x)
- || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
- DECL_PACKED (x) = 1;
+ else if (DECL_C_BIT_FIELD (field)
+ || TYPE_ALIGN (TREE_TYPE (field)) > BITS_PER_UNIT)
+ DECL_PACKED (field) = 1;
}
- if (DECL_C_BIT_FIELD (x)
- && integer_zerop (DECL_BIT_FIELD_REPRESENTATIVE (x)))
+ if (DECL_C_BIT_FIELD (field)
+ && integer_zerop (DECL_BIT_FIELD_REPRESENTATIVE (field)))
/* We don't treat zero-width bitfields as making a class
non-empty. */
;
- else if (field_poverlapping_p (x) && is_empty_class (type))
- {
- /* Empty data members also don't make a class non-empty. */
- CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
- }
+ else if (field_poverlapping_p (field) && is_empty_class (type))
+ /* Empty data members also don't make a class non-empty. */
+ CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
else
{
@@ -3632,6 +3631,6 @@ check_field_decls (tree t, tree *access_
/* The class is not even nearly empty. */
CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
- /* If one of the data members contains an empty class,
- so does T. */
+ /* If one of the data members contains an empty class, so
+ does T. */
if (CLASS_TYPE_P (type)
&& CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
@@ -3644,5 +3643,5 @@ check_field_decls (tree t, tree *access_
if (TYPE_PTR_P (type)
&& !TYPE_PTRFN_P (type))
- has_pointers = true;
+ pointer_member = field;
if (CLASS_TYPE_P (type))
@@ -3654,21 +3653,15 @@ check_field_decls (tree t, tree *access_
}
- if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
+ if (DECL_MUTABLE_P (field) || TYPE_HAS_MUTABLE_P (type))
CLASSTYPE_HAS_MUTABLE (t) = 1;
- if (DECL_MUTABLE_P (x))
+ if (DECL_MUTABLE_P (field))
{
- if (CP_TYPE_CONST_P (type))
- {
- error ("member %q+D cannot be declared both %<const%> "
- "and %<mutable%>", x);
- continue;
- }
if (TYPE_REF_P (type))
- {
- error ("member %q+D cannot be declared as a %<mutable%> "
- "reference", x);
- continue;
- }
+ error ("member %q+D cannot be declared as a %<mutable%> "
+ "reference", field);
+ else if (CP_TYPE_CONST_P (type))
+ error ("member %q+D cannot be declared both %<const%> "
+ "and %<mutable%>", field);
}
@@ -3678,5 +3671,5 @@ check_field_decls (tree t, tree *access_
CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
- if (field_poverlapping_p (x))
+ if (field_poverlapping_p (field))
/* A potentially-overlapping non-static data member makes the class
non-layout-POD. */
@@ -3691,13 +3684,19 @@ check_field_decls (tree t, tree *access_
/* We set DECL_C_BIT_FIELD in grokbitfield.
If the type and width are valid, we'll also set DECL_BIT_FIELD. */
- if (DECL_C_BIT_FIELD (x))
- check_bitfield_decl (x);
+ if (DECL_C_BIT_FIELD (field))
+ check_bitfield_decl (field);
- if (check_field_decl (x, t, cant_have_const_ctor_p, no_const_asn_ref_p))
+ if (check_field_decl (field, t,
+ cant_have_const_ctor_p, no_const_asn_ref_p))
{
- if (any_default_members
+ if (default_init_member
&& TREE_CODE (t) == UNION_TYPE)
- error ("multiple fields in union %qT initialized", t);
- any_default_members = true;
+ {
+ error ("multiple fields in union %qT initialized", t);
+ inform (DECL_SOURCE_LOCATION (default_init_member),
+ "initialized member %q+D declared here",
+ default_init_member);
+ }
+ default_init_member = field;
}
@@ -3705,12 +3704,12 @@ check_field_decls (tree t, tree *access_
anything left in DECL_INITIAL is an NSDMI that makes the class
non-aggregate in C++11. */
- if (DECL_INITIAL (x) && cxx_dialect < cxx14)
+ if (DECL_INITIAL (field) && cxx_dialect < cxx14)
CLASSTYPE_NON_AGGREGATE (t) = true;
- /* If any field is const, the structure type is pseudo-const. */
if (CP_TYPE_CONST_P (type))
{
+ /* If any field is const, the structure type is pseudo-const. */
C_TYPE_FIELDS_READONLY (t) = 1;
- if (DECL_INITIAL (x) == NULL_TREE)
+ if (DECL_INITIAL (field) == NULL_TREE)
SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
if (cxx_dialect < cxx11)
@@ -3736,8 +3735,8 @@ check_field_decls (tree t, tree *access_
different name from the class iff the class has a
user-declared constructor. */
- if (constructor_name_p (DECL_NAME (x), t)
+ if (constructor_name_p (DECL_NAME (field), t)
&& TYPE_HAS_USER_CONSTRUCTOR (t))
- permerror (DECL_SOURCE_LOCATION (x),
- "field %q#D with same name as class", x);
+ permerror (DECL_SOURCE_LOCATION (field),
+ "field %q#D with same name as class", field);
}
@@ -3762,26 +3761,29 @@ check_field_decls (tree t, tree *access_
This seems enough for practical purposes. */
if (warn_ecpp
- && has_pointers
+ && pointer_member
&& TYPE_HAS_USER_CONSTRUCTOR (t)
&& TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
&& !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
{
- warning (OPT_Weffc__, "%q#T has pointer data members", t);
-
- if (! TYPE_HAS_COPY_CTOR (t))
+ if (warning (OPT_Weffc__, "%q#T has pointer data members", t))
{
- warning (OPT_Weffc__,
- " but does not override %<%T(const %T&)%>", t, t);
- if (!TYPE_HAS_COPY_ASSIGN (t))
- warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
- }
- else if (! TYPE_HAS_COPY_ASSIGN (t))
- warning (OPT_Weffc__,
- " but does not override %<operator=(const %T&)%>", t);
+ if (! TYPE_HAS_COPY_CTOR (t))
+ {
+ warning (OPT_Weffc__,
+ " but does not override %<%T(const %T&)%>", t, t);
+ if (!TYPE_HAS_COPY_ASSIGN (t))
+ warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
+ }
+ else if (! TYPE_HAS_COPY_ASSIGN (t))
+ warning (OPT_Weffc__,
+ " but does not override %<operator=(const %T&)%>", t);
+ inform (DECL_SOURCE_LOCATION (pointer_member),
+ "pointer member %q+D declared here", pointer_member);
+ }
}
/* Non-static data member initializers make the default constructor
non-trivial. */
- if (any_default_members)
+ if (default_init_member)
{
TYPE_NEEDS_CONSTRUCTING (t) = true;
===================================================================
@@ -0,0 +1,10 @@
+// instantiation cannot turn a data member into a function!
+
+typedef int (frib) (int);
+
+template <typename T> class X
+{
+ T v; // { dg-error "declared function" }
+};
+
+X<frib> v;