+ if the identifier node is a valid attribute namespace for the string.
+ ATTR_NS "" stands for standard attribute (NULL IDENT) or "gnu"
+ namespace. */
+
+static inline bool
+is_attribute_namespace_p (const char *attr_ns, const_tree attr)
+{
+ tree ident = get_attribute_namespace (attr);
+ if (attr_ns == NULL)
+ return ident == NULL_TREE;
+ if (attr_ns[0])
+ return ident && is_attribute_p (attr_ns, ident);
+ return ident == NULL_TREE || is_attribute_p ("gnu", ident);
+}
+
/* Given an attribute name ATTR_NAME and a list of attributes LIST,
return a pointer to the attribute's list element if the attribute
is part of the list, or NULL_TREE if not found. If the attribute
@@ -217,7 +233,8 @@ lookup_attribute (const char *attr_name,
}
}
-/* Similar to lookup_attribute, but also match the attribute namespace. */
+/* Similar to lookup_attribute, but also match the attribute namespace.
+ ATTR_NS "" stands for either standard attribute or "gnu" namespace. */
static inline tree
lookup_attribute (const char *attr_ns, const char *attr_name, tree list)
--- gcc/attribs.cc.jj 2022-10-04 23:13:10.289090796 +0200
+++ gcc/attribs.cc 2022-10-06 20:23:35.693713861 +0200
@@ -1645,7 +1645,8 @@ remove_attribute (const char *attr_name,
return list;
}
-/* Similarly but also match namespace on the removed attributes. */
+/* Similarly but also match namespace on the removed attributes.
+ ATTR_NS "" stands for NULL or "gnu" namespace. */
tree
remove_attribute (const char *attr_ns, const char *attr_name, tree list)
@@ -1659,15 +1660,11 @@ remove_attribute (const char *attr_ns, c
tree l = *p;
tree attr = get_attribute_name (l);
- if (is_attribute_p (attr_name, attr))
+ if (is_attribute_p (attr_name, attr)
+ && is_attribute_namespace_p (attr_ns, l))
{
- tree ns = get_attribute_namespace (l);
- if ((ns == NULL_TREE && attr_ns == NULL)
- || (ns && attr_ns && is_attribute_p (attr_ns, ns)))
- {
- *p = TREE_CHAIN (l);
- continue;
- }
+ *p = TREE_CHAIN (l);
+ continue;
}
p = &TREE_CHAIN (l);
}
@@ -2088,14 +2085,20 @@ private_lookup_attribute (const char *at
tree ns = get_attribute_namespace (list);
if (ns == NULL_TREE)
{
- if (attr_ns == NULL)
+ if (attr_ns_len == 0)
break;
}
else if (attr_ns)
{
ident_len = IDENTIFIER_LENGTH (ns);
- if (cmp_attribs (attr_ns, attr_ns_len, IDENTIFIER_POINTER (ns),
- ident_len))
+ if (attr_ns_len == 0)
+ {
+ if (cmp_attribs ("gnu", strlen ("gnu"),
+ IDENTIFIER_POINTER (ns), ident_len))
+ break;
+ }
+ else if (cmp_attribs (attr_ns, attr_ns_len,
+ IDENTIFIER_POINTER (ns), ident_len))
break;
}
}
--- gcc/c-family/c-common.cc.jj 2022-10-06 17:43:47.880502941 +0200
+++ gcc/c-family/c-common.cc 2022-10-06 20:24:17.220152623 +0200
@@ -6008,12 +6008,12 @@ attribute_fallthrough_p (tree attr)
{
if (attr == error_mark_node)
return false;
- tree t = lookup_attribute ("fallthrough", attr);
+ tree t = lookup_attribute ("", "fallthrough", attr);
if (t == NULL_TREE)
return false;
/* It is no longer true that "this attribute shall appear at most once in
each attribute-list", but we still give a warning. */
- if (lookup_attribute ("fallthrough", TREE_CHAIN (t)))
+ if (lookup_attribute ("", "fallthrough", TREE_CHAIN (t)))
warning (OPT_Wattributes, "attribute %<fallthrough%> specified multiple "
"times");
/* No attribute-argument-clause shall be present. */
@@ -6024,7 +6024,8 @@ attribute_fallthrough_p (tree attr)
for (t = attr; t != NULL_TREE; t = TREE_CHAIN (t))
{
tree name = get_attribute_name (t);
- if (!is_attribute_p ("fallthrough", name))
+ if (!is_attribute_p ("fallthrough", name)
+ || !is_attribute_namespace_p ("", t))
{
if (!c_dialect_cxx () && get_attribute_namespace (t) == NULL_TREE)
/* The specifications of standard attributes in C mean
--- gcc/cp/parser.cc.jj 2022-10-06 17:43:42.418576616 +0200
+++ gcc/cp/parser.cc 2022-10-06 20:25:01.004560878 +0200
@@ -29265,7 +29265,8 @@ cp_parser_check_std_attribute (location_
if (attributes)
for (const auto &a : alist)
if (is_attribute_p (a, get_attribute_name (attribute))
- && lookup_attribute (a, attributes))
+ && is_attribute_namespace_p ("", attribute)
+ && lookup_attribute ("", a, attributes))
{
if (!from_macro_expansion_at (loc))
warning_at (loc, OPT_Wattributes, "attribute %qs specified "
--- gcc/cp/cp-gimplify.cc.jj 2022-10-06 17:43:42.413576684 +0200
+++ gcc/cp/cp-gimplify.cc 2022-10-06 20:24:43.145802239 +0200
@@ -3027,7 +3027,7 @@ cp_fold (tree x)
return x;
}
-/* Look up either "hot" or "cold" in attribute list LIST. */
+/* Look up "hot", "cold", "likely" or "unlikely" in attribute list LIST. */
tree
lookup_hotness_attribute (tree list)
@@ -3035,24 +3035,36 @@ lookup_hotness_attribute (tree list)
for (; list; list = TREE_CHAIN (list))
{
tree name = get_attribute_name (list);
- if (is_attribute_p ("hot", name)
- || is_attribute_p ("cold", name)
- || is_attribute_p ("likely", name)
- || is_attribute_p ("unlikely", name))
+ if ((is_attribute_p ("hot", name)
+ || is_attribute_p ("cold", name)
+ || is_attribute_p ("likely", name)
+ || is_attribute_p ("unlikely", name))
+ && is_attribute_namespace_p ("", list))
break;
}
return list;
}
-/* Remove both "hot" and "cold" attributes from LIST. */
+/* Remove "hot", "cold", "likely" and "unlikely" attributes from LIST. */
static tree
remove_hotness_attribute (tree list)
{
- list = remove_attribute ("hot", list);
- list = remove_attribute ("cold", list);
- list = remove_attribute ("likely", list);
- list = remove_attribute ("unlikely", list);
+ for (tree *p = &list; *p; )
+ {
+ tree l = *p;
+ tree name = get_attribute_name (l);
+ if ((is_attribute_p ("hot", name)
+ || is_attribute_p ("cold", name)
+ || is_attribute_p ("likely", name)
+ || is_attribute_p ("unlikely", name))
+ && is_attribute_namespace_p ("", l))
+ {
+ *p = TREE_CHAIN (l);
+ continue;
+ }
+ p = &TREE_CHAIN (l);
+ }
return list;
}
--- gcc/testsuite/g++.dg/cpp1z/fallthrough2.C.jj 2022-10-06 17:45:55.452782142 +0200
+++ gcc/testsuite/g++.dg/cpp1z/fallthrough2.C 2022-10-06 17:45:55.452782142
+0200
@@ -0,0 +1,24 @@
+// { dg-do compile { target c++17 } }
+// { dg-options "-Wextra -Wall -Wpedantic" }
+
+int
+foo (int i)
+{
+ switch (i)
+ {
+ case 2:
+ ++i;
+ [[fallthrough, whatever::fallthrough]]; // { dg-bogus "attribute
'fallthrough' specified multiple times" }
+ case 3: // { dg-warning "'fallthrough'
attribute ignored" "" { target *-*-* } .-1 }
+ ++i;
+ [[fallthrough, whatever2::fallthrough(1, 2, 3)]]; // { dg-bogus
"attribute 'fallthrough' specified multiple times" }
+ case 4: // { dg-warning "'fallthrough'
attribute ignored" "" { target *-*-* } .-1 }
+ [[whatever3::fallthrough("abcd")]]; // { dg-warning "attributes at
the beginning of statement are ignored" }
+ case 5:
+ [[whatever4::fallthrough]]; // { dg-bogus "attribute
'fallthrough' not preceding a case label or default label" }
+ ++i; // { dg-warning "attributes at the
beginning of statement are ignored" "" { target *-*-* } .-1 }
+ default:
+ break;
+ }
+ return i;
+}
--- gcc/testsuite/g++.dg/cpp2a/attr-likely7.C.jj 2022-10-06
17:45:55.452782142 +0200
+++ gcc/testsuite/g++.dg/cpp2a/attr-likely7.C 2022-10-06 17:45:55.452782142
+0200
@@ -0,0 +1,38 @@
+// { dg-do compile { target c++20 } }
+// { dg-additional-options -fdump-tree-gimple }
+// { dg-final { scan-tree-dump-times "hot label" 5 "gimple" } }
+// { dg-final { scan-tree-dump-times "cold label" 3 "gimple" } }
+
+bool b;
+
+template <class T> int f()
+{
+ if (b)
+ [[likely, whatever::unlikely ("abcd")]] return 0; // { dg-bogus
"ignoring attribute 'unlikely' after earlier 'likely'" }
+ else // { dg-warning "attributes at
the beginning of statement are ignored" "" { target *-*-* } .-1 }
+ [[unlikely, whatever2::hot]] flabel: return 1; // { dg-warning
"'whatever2::hot' scoped attribute directive ignored" }
+ switch (b)
+ {
+ [[likely, whatever3::cold (1, 2, 3)]] case true: break; // { dg-warning
"'whatever3::cold' scoped attribute directive ignored" }
+ };
+ return 1;
+}
+
+int main()
+{
+ if (b)
+ [[whatever4::unlikely (1), likely]] return 0; // { dg-bogus
"ignoring attribute 'likely' after earlier 'unlikely'" }
+ else if (b) // { dg-warning "attributes at
the beginning of statement are ignored" "" { target *-*-* } .-1 }
+ [[whatever5::hot, unlikely]] elabel: // { dg-warning
"'whatever5::hot' scoped attribute directive ignored" }
+ return 1;
+ else
+ [[whatever6::cold, likely]] b = false; // { dg-bogus
"ignoring attribute 'likely' after earlier 'cold'" }
+ // { dg-warning "attributes at
the beginning of statement are ignored" "" { target *-*-* } .-1 }
+ f<int>();
+
+ switch (b)
+ {
+ [[whatever7::unlikely (1), likely]] case true: break; // { dg-warning
"'whatever7::unlikely' scoped attribute directive ignored" }
+ [[whatever8::unlikely, unlikely]] case false: break; // { dg-bogus
"attribute 'unlikely' specified multiple times" }
+ }; // { dg-warning
"'whatever8::unlikely' scoped attribute directive ignored" "" { target *-*-* }
.-1 }
+}
Jakub
