On 4/29/22 10:12, Marek Polacek wrote:
[dcl.dcl]/5 says that
enum { };
is ill-formed, and since r197742 we issue a pedwarn. However, the
pedwarn also fires for
enum { } x;
which is well-formed. So only warn when {} is followed by a ;. This
should be correct since you can't have "enum {}, <whatever>" -- that
produces "expected unqualified-id before ',' token".
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? I think
this could go to 12.2 and 11.4 too.
OK.
PR c++/67048
gcc/cp/ChangeLog:
* parser.cc (cp_parser_enum_specifier): Warn about empty unnamed enum
only when it's followed by a semicolon.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/enum42.C: New test.
---
gcc/cp/parser.cc | 4 +++-
gcc/testsuite/g++.dg/cpp0x/enum42.C | 7 +++++++
2 files changed, 10 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/enum42.C
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 2235da10c7c..0fa37fdfb66 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -21007,7 +21007,9 @@ cp_parser_enum_specifier (cp_parser* parser)
/* If the next token is not '}', then there are some enumerators. */
else if (cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_BRACE))
{
- if (is_unnamed && !scoped_enum_p)
+ if (is_unnamed && !scoped_enum_p
+ /* Don't warn for enum {} a; here. */
+ && cp_lexer_nth_token_is (parser->lexer, 2, CPP_SEMICOLON))
pedwarn (type_start_token->location, OPT_Wpedantic,
"ISO C++ forbids empty unnamed enum");
}
diff --git a/gcc/testsuite/g++.dg/cpp0x/enum42.C
b/gcc/testsuite/g++.dg/cpp0x/enum42.C
new file mode 100644
index 00000000000..05b372a1947
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/enum42.C
@@ -0,0 +1,7 @@
+// PR c++/67048
+// { dg-do compile { target c++11 } }
+// { dg-options -Wpedantic }
+
+typedef enum {} X;
+enum {} x;
+enum {} y, z;
base-commit: 9ae8b993cd362e8aea4f65580aaf1453120207f2
