Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
I'm not certain OPT_Wc__20_extensions is the best thing for something
from [diff.cpp17]; would you prefer something else?
-- >8 --
Since my r11-532 changes to implement DR2237, for this test:
template<typename T>
struct S {
S<T>();
};
in C++20 we emit the ugly:
q.C:3:8: error: expected unqualified-id before ')' token
3 | S<T>();
which doesn't explain what the problem is. This patch improves that
diagnostic, reduces the error to a pedwarn, and adds a -Wc++20-compat
diagnostic. We now say:
q.C:3:7: warning: template-id not allowed for constructor [-Wc++20-extensions]
3 | S<T>();
This patch does *not* fix
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97202#c8>
where the C++20 diagnostic is missing altogether. Something for the
next stage1 I reckon.
-Wc++20-compat triggered in libitm/; I sent a patch for that.
DR 2237
PR c++/107126
PR c++/97202
gcc/cp/ChangeLog:
* parser.cc (cp_parser_unqualified_id): Downgrade the DR2237 error to
a pedwarn. Emit a -Wc++20-compat message.
(cp_parser_constructor_declarator_p): Likewise.
gcc/testsuite/ChangeLog:
* g++.dg/DRs/dr2237.C: Adjust dg-error.
* g++.dg/parse/constructor2.C: Likewise.
* g++.dg/template/error34.C: Likewise.
* g++.old-deja/g++.pt/ctor2.C: Likewise.
* g++.dg/DRs/dr2237-2.C: New test.
* g++.dg/DRs/dr2237-3.C: New test.
* g++.dg/DRs/dr2237-4.C: New test.
* g++.dg/diagnostic/cdtor-template1.C: New test.
---
gcc/cp/parser.cc | 33 ++++++++++++++-----
gcc/testsuite/g++.dg/DRs/dr2237-2.C | 9 +++++
gcc/testsuite/g++.dg/DRs/dr2237-3.C | 16 +++++++++
gcc/testsuite/g++.dg/DRs/dr2237-4.C | 11 +++++++
gcc/testsuite/g++.dg/DRs/dr2237.C | 2 +-
.../g++.dg/diagnostic/cdtor-template1.C | 9 +++++
gcc/testsuite/g++.dg/parse/constructor2.C | 16 ++++-----
gcc/testsuite/g++.dg/template/error34.C | 10 +++---
gcc/testsuite/g++.old-deja/g++.pt/ctor2.C | 2 +-
9 files changed, 85 insertions(+), 23 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/DRs/dr2237-2.C
create mode 100644 gcc/testsuite/g++.dg/DRs/dr2237-3.C
create mode 100644 gcc/testsuite/g++.dg/DRs/dr2237-4.C
create mode 100644 gcc/testsuite/g++.dg/diagnostic/cdtor-template1.C
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 3748ccd49ff..4f7d4edbad9 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -6717,12 +6717,17 @@ cp_parser_unqualified_id (cp_parser* parser,
/* DR 2237 (C++20 only): A simple-template-id is no longer valid as the
declarator-id of a constructor or destructor. */
- if (token->type == CPP_TEMPLATE_ID && declarator_p
- && cxx_dialect >= cxx20)
+ if (token->type == CPP_TEMPLATE_ID && declarator_p)
{
- if (!cp_parser_simulate_error (parser))
- error_at (tilde_loc, "template-id not allowed for destructor");
- return error_mark_node;
+ if (cxx_dialect >= cxx20)
+ {
+ if (!cp_parser_simulate_error (parser))
+ pedwarn (tilde_loc, OPT_Wc__20_extensions,
+ "template-id not allowed for destructor");
+ return error_mark_node;
+ }
+ warning_at (tilde_loc, OPT_Wc__20_compat,
+ "template-id not allowed for destructor in C++20");
}
/* If there was an explicit qualification (S::~T), first look
@@ -32329,11 +32334,11 @@ cp_parser_constructor_declarator_p (cp_parser
*parser, cp_parser_flags flags,
if (next_token->type != CPP_NAME
&& next_token->type != CPP_SCOPE
&& next_token->type != CPP_NESTED_NAME_SPECIFIER
- /* DR 2237 (C++20 only): A simple-template-id is no longer valid as the
- declarator-id of a constructor or destructor. */
- && (next_token->type != CPP_TEMPLATE_ID || cxx_dialect >= cxx20))
+ && next_token->type != CPP_TEMPLATE_ID)
return false;
+ const bool saw_template_id = (next_token->type == CPP_TEMPLATE_ID);
+
/* Parse tentatively; we are going to roll back all of the tokens
consumed here. */
cp_parser_parse_tentatively (parser);
@@ -32550,6 +32555,18 @@ cp_parser_constructor_declarator_p (cp_parser *parser,
cp_parser_flags flags,
/* We did not really want to consume any tokens. */
cp_parser_abort_tentative_parse (parser);
+ /* DR 2237 (C++20 only): A simple-template-id is no longer valid as the
+ declarator-id of a constructor or destructor. */
+ if (constructor_p && saw_template_id)
+ {
+ if (cxx_dialect >= cxx20)
+ pedwarn (input_location, OPT_Wc__20_extensions,
+ "template-id not allowed for constructor");
+ else
+ warning (OPT_Wc__20_compat,
+ "template-id not allowed for constructor in C++20");
+ }
+
return constructor_p;
}
diff --git a/gcc/testsuite/g++.dg/DRs/dr2237-2.C
b/gcc/testsuite/g++.dg/DRs/dr2237-2.C
new file mode 100644
index 00000000000..1d99347229c
--- /dev/null
+++ b/gcc/testsuite/g++.dg/DRs/dr2237-2.C
@@ -0,0 +1,9 @@
+// DR 2237 - Can a template-id name a constructor?
+// { dg-options "" }
+
+template<class T>
+struct X {
+ X<T>(); // { dg-warning "template-id not allowed for constructor" "" {
target c++20 } }
+ X(int); // OK, injected-class-name used
+ ~X<T>(); // { dg-warning "template-id not allowed for destructor" "" {
target c++20 } }
+};
diff --git a/gcc/testsuite/g++.dg/DRs/dr2237-3.C
b/gcc/testsuite/g++.dg/DRs/dr2237-3.C
new file mode 100644
index 00000000000..c8ad6852389
--- /dev/null
+++ b/gcc/testsuite/g++.dg/DRs/dr2237-3.C
@@ -0,0 +1,16 @@
+// PR c++/107126
+// { dg-options "" }
+
+template<typename T>
+struct C
+{
+ ~C();
+};
+template<typename T>
+C<T>::~C<T>() // { dg-warning "template-id not allowed for destructor"
"" { target c++20 } }
+{
+}
+int main()
+{
+ C<int> c;;
+}
diff --git a/gcc/testsuite/g++.dg/DRs/dr2237-4.C
b/gcc/testsuite/g++.dg/DRs/dr2237-4.C
new file mode 100644
index 00000000000..a358dd521b5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/DRs/dr2237-4.C
@@ -0,0 +1,11 @@
+// PR c++/97202
+// { dg-options "" }
+
+template<typename T>
+struct F
+{
+ F<T>(); // { dg-warning "template-id not allowed for constructor" "" {
target c++20 } }
+};
+
+template<typename T>
+inline F<T>::F() { }
diff --git a/gcc/testsuite/g++.dg/DRs/dr2237.C
b/gcc/testsuite/g++.dg/DRs/dr2237.C
index f3d6d11e61e..830c8f5a2a6 100644
--- a/gcc/testsuite/g++.dg/DRs/dr2237.C
+++ b/gcc/testsuite/g++.dg/DRs/dr2237.C
@@ -2,7 +2,7 @@
template<class T>
struct X {
- X<T>(); // { dg-error "expected" "" { target c++20 } }
+ X<T>(); // { dg-error "template-id not allowed for constructor" "" { target
c++20 } }
X(int); // OK, injected-class-name used
~X<T>(); // { dg-error "template-id not allowed for destructor" "" { target
c++20 } }
};
diff --git a/gcc/testsuite/g++.dg/diagnostic/cdtor-template1.C
b/gcc/testsuite/g++.dg/diagnostic/cdtor-template1.C
new file mode 100644
index 00000000000..429490708bc
--- /dev/null
+++ b/gcc/testsuite/g++.dg/diagnostic/cdtor-template1.C
@@ -0,0 +1,9 @@
+// PR c++/107126
+// { dg-do compile }
+// { dg-options "-Wc++20-compat" }
+
+template<class T>
+struct X {
+ X<T>(); // { dg-warning "template-id not allowed for constructor" }
+ ~X<T>(); // { dg-warning "template-id not allowed for destructor" }
+};
diff --git a/gcc/testsuite/g++.dg/parse/constructor2.C
b/gcc/testsuite/g++.dg/parse/constructor2.C
index d620f41e027..e4b2ad3f2fe 100644
--- a/gcc/testsuite/g++.dg/parse/constructor2.C
+++ b/gcc/testsuite/g++.dg/parse/constructor2.C
@@ -1,11 +1,11 @@
// PR c++/14260
-template <class TClass>
-class T
-{
-public:
- T(short,short f=0) {}
- T<TClass>(int f) {} // { dg-error "expected" "" { target c++20 } }
- T<TClass>(int f=0,const char* b=0) {} // { dg-error "expected" "" { target
c++20 } }
-};
+template <class TClass>
+class T
+{
+public:
+ T(short,short f=0) {}
+ T<TClass>(int f) {} // { dg-error "template-id not allowed for constructor"
"" { target c++20 } }
+ T<TClass>(int f=0,const char* b=0) {} // { dg-error "template-id not allowed
for constructor" "" { target c++20 } }
+};
diff --git a/gcc/testsuite/g++.dg/template/error34.C
b/gcc/testsuite/g++.dg/template/error34.C
index ab688d9ba8c..921cb8fb729 100644
--- a/gcc/testsuite/g++.dg/template/error34.C
+++ b/gcc/testsuite/g++.dg/template/error34.C
@@ -3,27 +3,27 @@
template<typename T> struct A
{
- A<__builtin_offsetof(T, x)>(); // { dg-error "type/value
mismatch|offsetof\\(T, x\\)|expected" }
+ A<__builtin_offsetof(T, x)>(); // { dg-error "type/value
mismatch|offsetof\\(T, x\\)|template-id" }
};
template<typename T> struct B
{
- B<__builtin_offsetof(T, x.y)>(); // { dg-error "type/value
mismatch|offsetof\\(T, x.y\\)|expected" }
+ B<__builtin_offsetof(T, x.y)>(); // { dg-error "type/value
mismatch|offsetof\\(T, x.y\\)|template-id" }
};
template<typename T> struct C
{
- C<__builtin_offsetof(T, x[6])>(); // { dg-error "type/value
mismatch|offsetof\\(T, x\\\[6\\\]\\)|expected" }
+ C<__builtin_offsetof(T, x[6])>(); // { dg-error "type/value
mismatch|offsetof\\(T, x\\\[6\\\]\\)|template-id" }
};
template<typename T> struct D
{
- D<__builtin_offsetof(T, x.y[6].z)>(); // { dg-error "type/value
mismatch|offsetof\\(T, x.y\\\[6\\\].z\\)|expected" }
+ D<__builtin_offsetof(T, x.y[6].z)>(); // { dg-error "type/value
mismatch|offsetof\\(T, x.y\\\[6\\\].z\\)|template-id" }
};
struct E { int x; };
template<typename T> struct F
{
- F<__builtin_offsetof(E, x)>(); // { dg-error "type/value
mismatch|offsetof\\(E, x\\)|expected" }
+ F<__builtin_offsetof(E, x)>(); // { dg-error "type/value
mismatch|offsetof\\(E, x\\)|template-id" }
};
diff --git a/gcc/testsuite/g++.old-deja/g++.pt/ctor2.C
b/gcc/testsuite/g++.old-deja/g++.pt/ctor2.C
index bf418ba48c7..56b4232d04b 100644
--- a/gcc/testsuite/g++.old-deja/g++.pt/ctor2.C
+++ b/gcc/testsuite/g++.old-deja/g++.pt/ctor2.C
@@ -4,7 +4,7 @@
template <class T>
struct A {
- A<T>(); // { dg-error "expected" "" { target c++20 } }
+ A<T>(); // { dg-error "template-id" "" { target c++20 } }
};
template <class T>
base-commit: 78005c648921899a674d1e561b49b05ccabedfe0
--
2.43.0
