https://gcc.gnu.org/g:7eb2acb7221b5a219ece1a693d9ac594f229a61a
commit r15-6334-g7eb2acb7221b5a219ece1a693d9ac594f229a61a
Author: Jakub Jelinek <ja...@redhat.com>
Date: Wed Dec 18 12:00:13 2024 +0100
c++: Fix up pedantic handling of alignas [PR110345]
The following patch on top of the PR110345 P2552R3 series
emits pedantic pedwarns for alignas appertaining to incorrect entities.
As the middle-end and attribute exclusions look for "aligned" attribute,
the patch transforms alignas into "internal "::aligned attribute (didn't
use [[aligned (x)]] so that people can't type it that way).
2024-12-18 Jakub Jelinek <ja...@redhat.com>
PR c++/110345
gcc/c-family/
* c-common.h (attr_aligned_exclusions): Declare.
(handle_aligned_attribute): Likewise.
* c-attribs.cc (handle_aligned_attribute): No longer
static.
(attr_aligned_exclusions): Use extern instead of static.
gcc/cp/
* cp-tree.h (enum cp_tree_index): Add CPTI_INTERNAL_IDENTIFIER.
(internal_identifier): Define.
(internal_attribute_table): Declare.
* parser.cc (cp_parser_exception_declaration): Error on alignas
on exception declaration.
(cp_parser_std_attribute_spec): Turn alignas into internal
ns aligned attribute rather than gnu.
* decl.cc (initialize_predefined_identifiers): Initialize
internal_identifier.
* tree.cc (handle_alignas_attribute): New function.
(internal_attributes): New variable.
(internal_attribute_table): Likewise.
* cp-objcp-common.h (cp_objcp_attribute_table): Add
internal_attribute_table entry.
gcc/testsuite/
* g++.dg/cpp0x/alignas1.C: Add dg-options "".
* g++.dg/cpp0x/alignas2.C: Likewise.
* g++.dg/cpp0x/alignas7.C: Likewise.
* g++.dg/cpp0x/alignas21.C: New test.
* g++.dg/ext/bitfield9.C: Expect a warning.
* g++.dg/cpp2a/is-layout-compatible3.C: Add dg-options -pedantic.
Expect a warning.
Diff:
---
gcc/c-family/c-attribs.cc | 5 +-
gcc/c-family/c-common.h | 2 +
gcc/cp/cp-objcp-common.h | 3 +-
gcc/cp/cp-tree.h | 3 +
gcc/cp/decl.cc | 1 +
gcc/cp/parser.cc | 12 +-
gcc/cp/tree.cc | 41 ++++++
gcc/testsuite/g++.dg/cpp0x/alignas1.C | 1 +
gcc/testsuite/g++.dg/cpp0x/alignas2.C | 1 +
gcc/testsuite/g++.dg/cpp0x/alignas21.C | 156 +++++++++++++++++++++
gcc/testsuite/g++.dg/cpp0x/alignas7.C | 1 +
gcc/testsuite/g++.dg/cpp2a/is-layout-compatible3.C | 3 +-
gcc/testsuite/g++.dg/ext/bitfield9.C | 2 +-
13 files changed, 223 insertions(+), 8 deletions(-)
diff --git a/gcc/c-family/c-attribs.cc b/gcc/c-family/c-attribs.cc
index eb76a9e1c66f..3bb2cb5f83c2 100644
--- a/gcc/c-family/c-attribs.cc
+++ b/gcc/c-family/c-attribs.cc
@@ -101,7 +101,6 @@ static tree handle_destructor_attribute (tree *, tree,
tree, int, bool *);
static tree handle_mode_attribute (tree *, tree, tree, int, bool *);
static tree handle_section_attribute (tree *, tree, tree, int, bool *);
static tree handle_special_var_sec_attribute (tree *, tree, tree, int, bool *);
-static tree handle_aligned_attribute (tree *, tree, tree, int, bool *);
static tree handle_warn_if_not_aligned_attribute (tree *, tree, tree,
int, bool *);
static tree handle_strict_flex_array_attribute (tree *, tree, tree,
@@ -195,7 +194,7 @@ static tree handle_null_terminated_string_arg_attribute
(tree *, tree, tree, int
{ name, function, type, variable }
/* Define attributes that are mutually exclusive with one another. */
-static const struct attribute_spec::exclusions attr_aligned_exclusions[] =
+extern const struct attribute_spec::exclusions attr_aligned_exclusions[] =
{
/* Attribute name exclusion applies to:
function, type, variable */
@@ -2816,7 +2815,7 @@ common_handle_aligned_attribute (tree *node, tree name,
tree args, int flags,
/* Handle a "aligned" attribute; arguments as in
struct attribute_spec.handler. */
-static tree
+tree
handle_aligned_attribute (tree *node, tree name, tree args,
int flags, bool *no_add_attrs)
{
diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index ac574e922e3b..13406e27609b 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -1666,8 +1666,10 @@ extern int parse_tm_stmt_attr (tree, int);
extern int tm_attr_to_mask (tree);
extern tree tm_mask_to_attr (int);
extern tree find_tm_attribute (tree);
+extern const struct attribute_spec::exclusions attr_aligned_exclusions[];
extern const struct attribute_spec::exclusions attr_cold_hot_exclusions[];
extern const struct attribute_spec::exclusions attr_noreturn_exclusions[];
+extern tree handle_aligned_attribute (tree *, tree, tree, int, bool *);
extern tree handle_noreturn_attribute (tree *, tree, tree, int, bool *);
extern tree handle_musttail_attribute (tree *, tree, tree, int, bool *);
extern bool has_attribute (location_t, tree, tree, tree (*)(tree));
diff --git a/gcc/cp/cp-objcp-common.h b/gcc/cp/cp-objcp-common.h
index e9c5ac40020c..5b3abb547d25 100644
--- a/gcc/cp/cp-objcp-common.h
+++ b/gcc/cp/cp-objcp-common.h
@@ -129,7 +129,8 @@ static const scoped_attribute_specs *const
cp_objcp_attribute_table[] =
&cxx_gnu_attribute_table,
&c_common_gnu_attribute_table,
&c_common_clang_attribute_table,
- &c_common_format_attribute_table
+ &c_common_format_attribute_table,
+ &internal_attribute_table
};
#undef LANG_HOOKS_ATTRIBUTE_TABLE
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index c5e0fc5c440d..6833035664b0 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -192,6 +192,7 @@ enum cp_tree_index
CPTI_HEAP_VEC_UNINIT_IDENTIFIER,
CPTI_HEAP_VEC_IDENTIFIER,
CPTI_OMP_IDENTIFIER,
+ CPTI_INTERNAL_IDENTIFIER,
CPTI_LANG_NAME_C,
CPTI_LANG_NAME_CPLUSPLUS,
@@ -345,6 +346,7 @@ extern GTY(()) tree cp_global_trees[CPTI_MAX];
#define heap_vec_uninit_identifier
cp_global_trees[CPTI_HEAP_VEC_UNINIT_IDENTIFIER]
#define heap_vec_identifier
cp_global_trees[CPTI_HEAP_VEC_IDENTIFIER]
#define omp_identifier cp_global_trees[CPTI_OMP_IDENTIFIER]
+#define internal_identifier
cp_global_trees[CPTI_INTERNAL_IDENTIFIER]
#define lang_name_c cp_global_trees[CPTI_LANG_NAME_C]
#define lang_name_cplusplus
cp_global_trees[CPTI_LANG_NAME_CPLUSPLUS]
@@ -8215,6 +8217,7 @@ extern bool is_byte_access_type (tree);
extern bool is_byte_access_type_not_plain_char (tree);
extern const struct scoped_attribute_specs cxx_gnu_attribute_table;
extern const struct scoped_attribute_specs std_attribute_table;
+extern const struct scoped_attribute_specs internal_attribute_table;
extern tree make_ptrmem_cst (tree, tree);
extern tree cp_build_type_attribute_variant (tree, tree);
extern tree cp_build_reference_type (tree, bool);
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 135747b75e2b..2716ac5495a5 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -4840,6 +4840,7 @@ initialize_predefined_identifiers (void)
{"heap [] uninit", &heap_vec_uninit_identifier, cik_normal},
{"heap []", &heap_vec_identifier, cik_normal},
{"omp", &omp_identifier, cik_normal},
+ {"internal ", &internal_identifier, cik_normal},
{NULL, NULL, cik_normal}
};
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 3f4b1e9e3e35..2ad6886af9c3 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -29945,7 +29945,15 @@ cp_parser_exception_declaration (cp_parser* parser)
tree decl = grokdeclarator (declarator, &type_specifiers, CATCHPARM, 1,
&type_specifiers.attributes);
if (decl != error_mark_node && type_specifiers.attributes)
- cplus_decl_attributes (&decl, type_specifiers.attributes, 0);
+ {
+ cplus_decl_attributes (&decl, type_specifiers.attributes, 0);
+ if (pedantic && lookup_attribute ("internal ", "aligned",
+ DECL_ATTRIBUTES (decl)))
+ pedwarn (type_specifiers.locations[ds_attribute]
+ ? type_specifiers.locations[ds_attribute]
+ : input_location, OPT_Wpedantic,
+ "%<alignas%> on exception declaration");
+ }
return decl;
}
@@ -31396,7 +31404,7 @@ cp_parser_std_attribute_spec (cp_parser *parser)
/* Build the C++-11 representation of an 'aligned'
attribute. */
attributes
- = build_tree_list (build_tree_list (gnu_identifier,
+ = build_tree_list (build_tree_list (internal_identifier,
aligned_identifier), alignas_expr);
}
diff --git a/gcc/cp/tree.cc b/gcc/cp/tree.cc
index 939d2b060fb4..97ce1f66d2fd 100644
--- a/gcc/cp/tree.cc
+++ b/gcc/cp/tree.cc
@@ -5114,6 +5114,35 @@ handle_likeliness_attribute (tree *node, tree name, tree
args,
return error_mark_node;
}
+/* The C++11 alignment specifier. It mostly maps to GNU aligned attribute,
+ but we need to do some extra pedantic checking. */
+
+static tree
+handle_alignas_attribute (tree *node, tree name, tree args, int flags,
+ bool *no_add_attrs)
+{
+ tree t = *node;
+ tree ret = handle_aligned_attribute (node, name, args, flags, no_add_attrs);
+ if (pedantic)
+ {
+ if (TREE_CODE (*node) == FUNCTION_DECL)
+ pedwarn (input_location, OPT_Wattributes,
+ "%<alignas%> on function declaration");
+ else if (TREE_CODE (*node) == ENUMERAL_TYPE)
+ pedwarn (input_location, OPT_Wattributes,
+ "%<alignas%> on enumerated type");
+ else if (TYPE_P (*node) && t != *node)
+ pedwarn (input_location, OPT_Wattributes,
+ "%<alignas%> on a type other than class");
+ else if (TREE_CODE (*node) == FIELD_DECL && DECL_C_BIT_FIELD (*node))
+ pedwarn (input_location, OPT_Wattributes, "%<alignas%> on bit-field");
+ else if (TREE_CODE (t) == TYPE_DECL)
+ pedwarn (input_location, OPT_Wattributes,
+ "%<alignas%> on a type alias");
+ }
+ return ret;
+}
+
/* Table of valid C++ attributes. */
static const attribute_spec cxx_gnu_attributes[] =
{
@@ -5162,6 +5191,18 @@ const scoped_attribute_specs std_attribute_table =
nullptr, { std_attributes }
};
+/* Table of internal attributes. */
+static const attribute_spec internal_attributes[] =
+{
+ { "aligned", 0, 1, false, false, false, false,
+ handle_alignas_attribute, attr_aligned_exclusions }
+};
+
+const scoped_attribute_specs internal_attribute_table =
+{
+ "internal ", { internal_attributes }
+};
+
/* Handle an "init_priority" attribute; arguments as in
struct attribute_spec.handler. */
static tree
diff --git a/gcc/testsuite/g++.dg/cpp0x/alignas1.C
b/gcc/testsuite/g++.dg/cpp0x/alignas1.C
index d73c875d6374..71380956d476 100644
--- a/gcc/testsuite/g++.dg/cpp0x/alignas1.C
+++ b/gcc/testsuite/g++.dg/cpp0x/alignas1.C
@@ -1,5 +1,6 @@
// PR c++/65734
// { dg-do compile { target c++11 } }
+// { dg-options "" }
template <class T> struct A
{
diff --git a/gcc/testsuite/g++.dg/cpp0x/alignas2.C
b/gcc/testsuite/g++.dg/cpp0x/alignas2.C
index 2e7d051c886d..b359154bfd44 100644
--- a/gcc/testsuite/g++.dg/cpp0x/alignas2.C
+++ b/gcc/testsuite/g++.dg/cpp0x/alignas2.C
@@ -1,5 +1,6 @@
// PR c++/65734
// { dg-do compile { target c++11 } }
+// { dg-options "" }
template <typename T>
struct BVector
diff --git a/gcc/testsuite/g++.dg/cpp0x/alignas21.C
b/gcc/testsuite/g++.dg/cpp0x/alignas21.C
new file mode 100644
index 000000000000..b7be7c5ce926
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/alignas21.C
@@ -0,0 +1,156 @@
+// C++ 26 P2552R3 - On the ignorability of standard attributes
+// { dg-do compile { target c++11 } }
+
+int arr[2];
+struct S { int a, b; };
+S arr2[2];
+
+void
+foo (int n)
+{
+ alignas (int) int x1;
+ alignas ("foobar") int x2; // { dg-error "'alignas'
argument has non-integral type 'const char \\\[7\\\]'" }
+ alignas (0) int x3; // { dg-warning "requested
alignment '0' is not a positive power of 2" }
+ alignas ("foo", "bar", "baz") int x4; // { dg-error
"'alignas' argument has non-integral type 'const char \\\[4\\\]'" }
+ // { dg-error "expected '\\\)'
before ',' token" "" { target *-*-* } .-1 }
+ // { dg-error "expected
declaration before ',' token" "" { target *-*-* } .-2 }
+ // { dg-error "expected
primary-expression before ',' token" "" { target *-*-* } .-3 }
+ alignas (0, 1, 2) int x5; // { dg-error "expected '\\\)'
before ',' token" }
+ // { dg-error "expected
declaration before ',' token" "" { target *-*-* } .-1 }
+ // { dg-error "expected
primary-expression before ',' token" "" { target *-*-* } .-2 }
+
+ auto a = [] alignas (int) () {}; // { dg-error "'alignas' on
function declaration" }
+ auto b = [] constexpr alignas (int) {}; // { dg-error "'alignas' on a
type other than class" }
+ // { dg-error "parameter
declaration before lambda declaration specifiers only optional with" "" {
target c++20_down } .-1 }
+ // { dg-error "'constexpr'
lambda only available with" "" { target c++14_down } .-2 }
+ auto c = [] noexcept alignas (int) {}; // { dg-error "'alignas' on a
type other than class" }
+ // { dg-error "parameter
declaration before lambda exception specification only optional with" "" {
target c++20_down } .-1 }
+ auto d = [] () alignas (int) {}; // { dg-error "'alignas' on a
type other than class" }
+ auto e = new int [n] alignas (int); // { dg-warning "attributes
ignored on outermost array type in new expression" }
+ auto e2 = new int [n] alignas (int) [42]; // { dg-warning "attributes
ignored on outermost array type in new expression" }
+ auto f = new int [n][42] alignas (int); // { dg-error "'alignas' on a
type other than class" }
+ alignas (int); // { dg-warning "attributes at
the beginning of statement are ignored" }
+ alignas (int) {} // { dg-warning "attributes at
the beginning of statement are ignored" }
+ alignas (int) if (true) {} // { dg-warning "attributes at
the beginning of statement are ignored" }
+ alignas (int) while (false) {} // { dg-warning "attributes at
the beginning of statement are ignored" }
+ alignas (int) goto lab; // { dg-warning "attributes at
the beginning of statement are ignored" }
+ alignas (int) lab:; // { dg-error "alignment may
not be specified for 'lab'" }
+ alignas (int) try {} catch (int) {} // { dg-warning "attributes at
the beginning of statement are ignored" }
+ if (alignas (int) int x = 0) {}
+ switch (n)
+ {
+ alignas (int) case 1: // { dg-error "alignment may
not be specified for" }
+ alignas (int) break; // { dg-warning "attributes at
the beginning of statement are ignored" }
+ alignas (int) default: // { dg-error "alignment may
not be specified for" }
+ break;
+ }
+ for (alignas (int) auto a : arr) {}
+ for (alignas (int) auto [a, b] : arr2) {} // { dg-error "structured
bindings only available with" "" { target c++14_down } }
+ alignas (int) asm (""); // { dg-warning "attributes
ignored on 'asm' declaration" }
+ try {} catch (alignas (int) int x) {} // { dg-error
"'alignas' on exception declaration" }
+ try {} catch (alignas (int) int) {} // { dg-error "'alignas' on
exception declaration" }
+ try {} catch (int alignas (int) x) {} // { dg-warning
"attribute ignored" }
+ try {} catch (int alignas (int)) {} // { dg-warning "attribute
ignored" }
+ try {} catch (int x alignas (int)) {} // { dg-error
"'alignas' on exception declaration" }
+}
+
+alignas (int) int bar (); // { dg-error "'alignas' on
function declaration" }
+using foobar alignas (int) = int; // { dg-error "'alignas' on a
type alias" }
+alignas (int) int a;
+alignas (int) auto [b, c] = arr; // { dg-error "structured
bindings only available with" "" { target c++14_down } }
+alignas (int); // { dg-warning "attribute
ignored" }
+inline alignas (int) void baz () {} // { dg-warning "attribute
ignored" }
+ // { dg-error "standard
attributes in middle of decl-specifiers" "" { target *-*-* } .-1 }
+constexpr alignas (int) int qux () { return 0; } // { dg-warning
"attribute ignored" }
+ // { dg-error "standard
attributes in middle of decl-specifiers" "" { target *-*-* } .-1 }
+int alignas (int) d; // { dg-warning "attribute
ignored" }
+int const alignas (int) e = 1; // { dg-warning "attribute
ignored" }
+struct A {} alignas (int); // { dg-warning "attribute
ignored in declaration of 'struct A'" }
+struct A alignas (int); // { dg-warning
"attribute ignored" }
+struct A alignas (int) a1; // { dg-warning "attribute
ignored" }
+A alignas (int) a2; // { dg-warning "attribute
ignored" }
+enum B { B0 } alignas (int); // { dg-warning "attribute
ignored in declaration of 'enum B'" }
+enum B alignas (int); // { dg-warning "attribute
ignored" }
+enum B alignas (int) b1; // { dg-warning "attribute
ignored" }
+B alignas (int) b2; // { dg-warning "attribute
ignored" }
+struct alignas (int) C {};
+int f alignas (int);
+struct alignas (int) Y;
+int g[2] alignas (int); // { dg-error
"'alignas' on a type other than class" }
+int g2 alignas (int) [2];
+int corge () alignas (int); // { dg-error "'alignas' on a
type other than class" }
+int *alignas (int) h; // { dg-error "'alignas' on a
type other than class" }
+int & alignas (int) i = f; // { dg-error "'alignas' on a
type other than class" }
+int S::* alignas (int) k; // { dg-error "'alignas' on a
type other than class" }
+auto l = sizeof (int [2] alignas (int)); // { dg-error "'alignas' on a
type other than class" }
+int freddy (alignas (int) int a, // { dg-error "alignment may
not be specified for 'a'" }
+ alignas (int) int, // { dg-error "alignment may
not be specified for '<anonymous>'" }
+ alignas (int) int c = 0, // { dg-error "alignment may
not be specified for 'c'" }
+ alignas (int) int = 0); // { dg-error "alignment may
not be specified for '<anonymous>'" }
+void
+corge (alignas (int) int a, // { dg-error "alignment may
not be specified for 'a'" }
+ alignas (int) int, // { dg-error "alignment may
not be specified for '<anonymous>'" }
+ alignas (int) int c = 0, // { dg-error
"alignment may not be specified for 'c'" }
+ alignas (int) int = 0) // { dg-error "alignment may
not be specified for '<anonymous>'" }
+{
+}
+alignas (int) void
+garply () // { dg-error "'alignas' on
function declaration" }
+{
+}
+int grault (int alignas (int) a, // { dg-warning "attribute
ignored" }
+ int alignas (int), // { dg-warning "attribute
ignored" }
+ int alignas (int) c = 0, // { dg-warning "attribute
ignored" }
+ int alignas (int) = 0); // { dg-warning "attribute
ignored" }
+void
+waldo (int alignas (int) a, // { dg-warning "attribute
ignored" }
+ int alignas (int), // { dg-warning "attribute
ignored" }
+ int alignas (int) c = 0, // { dg-warning
"attribute ignored" }
+ int alignas (int) = 0) // { dg-warning "attribute
ignored" }
+{
+}
+int plugh (int a alignas (int), // { dg-error
"alignment may not be specified for 'a'" }
+ int b alignas (int) = 0); // { dg-error "alignment may
not be specified for 'b'" }
+void
+thud (int a alignas (int), // { dg-error "alignment may
not be specified for 'a'" }
+ int b alignas (int) = 0) // { dg-error "alignment may
not be specified for 'b'" }
+{
+}
+enum alignas (int) D { D0 }; // { dg-error "'alignas' on
enumerated type" }
+enum class alignas (int) E { E0 }; // { dg-error "'alignas' on
enumerated type" }
+enum F {};
+enum alignas (int) F; // { dg-warning "type
attributes ignored after type is already defined" }
+enum G {
+ G0 alignas (int), // { dg-error "alignment may
not be specified for 'G0'" }
+ G1 alignas (int) = 2 // { dg-error "alignment may
not be specified for 'G1'" }
+};
+namespace alignas (int) H { using H0 = int; } // { dg-error "expected
identifier before 'alignas'" }
+ // { dg-error "H' does not name
a type" "" { target *-*-* } .-1 }
+namespace alignas (int) {} // { dg-error "expected
identifier before 'alignas'" }
+ // { dg-error "expected
unqualified-id before '\\\{' token" "" { target *-*-* } .-1 }
+alignas (int) using namespace H;
+ // { dg-error "'H' is not a
namespace-name" "" { target *-*-* } .-1 }
+struct alignas (int) I
+{
+ alignas (int); // { dg-error "declaration does
not declare anything" }
+ alignas (int) int i;
+ alignas (int) int foo (); // { dg-error "'alignas' on
function declaration" }
+ alignas (int) int bar () { return 1; } // { dg-error "'alignas' on
function declaration" }
+ alignas (int) int : 0; // { dg-error "'alignas' on
bit-field" }
+ alignas (int) int i2 : 5; // { dg-error "'alignas' on
bit-field" }
+ alignas (int) static int i3;
+ static int i4;
+};
+alignas (int) int I::i4 = 0;
+struct J : alignas (int) C {}; // { dg-warning "attributes on
base specifiers are ignored" }
+#if __cpp_concepts >= 201907L
+template <typename T>
+concept K alignas (int) = requires { true; }; // { dg-error "alignment may
not be specified for 'K'" "" { target c++20 } }
+#endif
+typedef int L alignas (int); // { dg-error "'alignas' on a
type alias" }
+template <typename T>
+struct M {};
+template <>
+struct alignas (int) M<int> { int m; };
+typedef int N[2] alignas (int); // { dg-error
"'alignas' on a type other than class" }
+typedef int O alignas (int) [2]; // { dg-error "'alignas' on a
type alias" }
diff --git a/gcc/testsuite/g++.dg/cpp0x/alignas7.C
b/gcc/testsuite/g++.dg/cpp0x/alignas7.C
index a209250af9b7..90cac3fe2433 100644
--- a/gcc/testsuite/g++.dg/cpp0x/alignas7.C
+++ b/gcc/testsuite/g++.dg/cpp0x/alignas7.C
@@ -1,5 +1,6 @@
// PR c++/71513
// { dg-do compile { target c++11 } }
+// { dg-options "" }
template < int N, typename T >
struct A
diff --git a/gcc/testsuite/g++.dg/cpp2a/is-layout-compatible3.C
b/gcc/testsuite/g++.dg/cpp2a/is-layout-compatible3.C
index 8f48ba8679a1..499ba4977d41 100644
--- a/gcc/testsuite/g++.dg/cpp2a/is-layout-compatible3.C
+++ b/gcc/testsuite/g++.dg/cpp2a/is-layout-compatible3.C
@@ -1,5 +1,6 @@
// P0466R5
// { dg-do compile { target c++20 } }
+// { dg-options "-pedantic" }
namespace std
{
@@ -34,7 +35,7 @@ union N { J v; };
union O { int a; int b; };
union P { int a : 1; int b : 12; };
enum Q : int { Q1, Q2 };
-enum alignas(16) R : int { R1, R2 };
+enum alignas(16) R : int { R1, R2 }; // { dg-warning "'alignas' on
enumerated type" }
struct U { [[no_unique_address]] S a1; [[no_unique_address]] S a2;
[[no_unique_address]] S a3; };
struct V { [[no_unique_address]] S b1; [[no_unique_address]] T b2;
[[no_unique_address]] S b3; };
struct alignas(16) A : public I {};
diff --git a/gcc/testsuite/g++.dg/ext/bitfield9.C
b/gcc/testsuite/g++.dg/ext/bitfield9.C
index 4a4ebf23c1fb..a3b1bf18e1be 100644
--- a/gcc/testsuite/g++.dg/ext/bitfield9.C
+++ b/gcc/testsuite/g++.dg/ext/bitfield9.C
@@ -3,7 +3,7 @@
struct S
{
- char a:4;
+ char a:4; // { dg-warning "alignas' on bit-field" "" {
target *-*-* } .+1 }
char b:8 alignas(int); // { dg-warning "ISO C\\+\\+ allows bit-field
attributes only before the ':' token" }
char c:8 [[gnu::aligned(8)]]; // { dg-warning "ISO C\\+\\+ allows
bit-field attributes only before the ':' token" }
// { dg-error "two consecutive '\\\[' shall
only introduce an attribute before '\\\[' token" "" { target *-*-* } .-1 }
