Re: [C++ PATCH] Pedwarn on a non-standard position of a C++ attribute.

[Ville Voutilainen]

On 24 May 2018 at 19:57, Nathan Sidwell <nat...@acm.org> wrote:
> On 05/24/2018 10:48 AM, Ville Voutilainen wrote:
>>
>> Tested manually on Linux-x64, finishing testing with the full suite
>> on Linux-PPC64. Ok for trunk?
>>
>> 2018-05-24  Ville Voutilainen  <ville.voutilai...@gmail.com>
>>
>>      gcc/cp/
>>
>>      Pedwarn on a non-standard position of a C++ attribute.
>>      * parser.c (cp_parser_namespace_definition): Pedwarn about attributes
>>      after the namespace name.
>>
>>      testsuite/
>>
>>      Pedwarn on a non-standard position of a C++ attribute.
>>      * g++.dg/cpp1z/namespace-attribs2.C: New.
>>
>
> ok, thanks

The full suite run revealed a couple of adjustments:

2018-05-24  Ville Voutilainen  <ville.voutilai...@gmail.com>

    gcc/cp/

    Pedwarn on a non-standard position of a C++ attribute.
    * parser.c (cp_parser_namespace_definition): Pedwarn about attributes
    after the namespace name.

    testsuite/

    Pedwarn on a non-standard position of a C++ attribute.
    * g++.dg/cpp0x/gen-attrs-56.C: Adjust.
    * g++.dg/cpp0x/gen-attrs-64.C: Likewise.
    * g++.dg/cpp1z/namespace-attribs2.C: New.

diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index 6f51f03..ac68159 100644
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -18588,6 +18588,11 @@ cp_parser_namespace_definition (cp_parser* parser)
 	{
 	  identifier = cp_parser_identifier (parser);
 
+	  if (cp_next_tokens_can_be_std_attribute_p (parser))
+	      pedwarn (input_location, OPT_Wpedantic,
+		       "standard attributes on namespaces must precede "
+		       "the namespace name");
+
 	  /* Parse any attributes specified after the identifier.  */
 	  attribs = attr_chainon (attribs, cp_parser_attributes_opt (parser));
 	}
diff --git a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-56.C b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-56.C
index f331ed3..f63fff4 100644
--- a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-56.C
+++ b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-56.C
@@ -2,4 +2,4 @@
 // { dg-do compile { target c++11 } }
 
 namespace foo __attribute__((visibility("default"))) {}
-namespace bar [[gnu::visibility("default")]] {}
+namespace [[gnu::visibility("default")]] bar {}
diff --git a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-64.C b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-64.C
index c0d48fc..4b335eb 100644
--- a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-64.C
+++ b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-64.C
@@ -1,4 +1,4 @@
 // PR c++/85140
 // { dg-do compile { target c++11 } }
 
-namespace N alignas() {}	// { dg-error "expected" }
+namespace alignas() N  {}	// { dg-error "expected" }
diff --git a/gcc/testsuite/g++.dg/cpp1z/namespace-attribs2.C b/gcc/testsuite/g++.dg/cpp1z/namespace-attribs2.C
new file mode 100644
index 0000000..2049da3
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/namespace-attribs2.C
@@ -0,0 +1,7 @@
+// { dg-options "-std=c++17" }
+// { dg-additional-options "-pedantic" }
+
+namespace B [[deprecated]] {} // { dg-warning "ignored|must precede" }
+
+namespace [[deprecated]] D {} // { dg-warning "ignored" }
+