Hi!
Another easy patch where c++2a just allows something we've already accepted
with a pedwarn.
Bootstrapped/regtested on x86_64-linux and i686-linux, including make
check-c++-all, ok for trunk?
2017-09-20 Jakub Jelinek <ja...@redhat.com>
P0409R2 - allow lambda capture [=, this]
* parser.c (cp_parser_lambda_introducer): For cxx2a don't pedwarn on
redundant [=, this].
* g++.dg/cpp1z/lambda-this1.C: Don't expect error for c++2a on [=, this]
capture. Add further tests.
* g++.dg/cpp0x/lambda/lambda-capture-redundancy.C: Don't expect error
for c++2a on [=, this] capture.
--- gcc/cp/parser.c.jj 2017-09-19 16:38:14.000000000 +0200
+++ gcc/cp/parser.c 2017-09-20 09:32:44.117646033 +0200
@@ -10183,7 +10183,8 @@ cp_parser_lambda_introducer (cp_parser*
if (cp_lexer_next_token_is_keyword (parser->lexer, RID_THIS))
{
location_t loc = cp_lexer_peek_token (parser->lexer)->location;
- if (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda_expr) == CPLD_COPY)
+ if (cxx_dialect < cxx2a
+ && LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda_expr) == CPLD_COPY)
pedwarn (loc, 0, "explicit by-copy capture of %<this%> redundant "
"with by-copy capture default");
cp_lexer_consume_token (parser->lexer);
--- gcc/testsuite/g++.dg/cpp1z/lambda-this1.C.jj 2016-09-27
21:09:59.000000000 +0200
+++ gcc/testsuite/g++.dg/cpp1z/lambda-this1.C 2017-09-20 09:52:54.893394307
+0200
@@ -17,13 +17,31 @@ struct A {
auto h = [*this] () mutable { a++; };// { dg-error "'*this' capture only
available with" "" { target c++14_down } }
auto i = [=] { return a; };
auto j = [&] { return a; };
- auto k = [=, this] { return a; };// { dg-error "explicit by-copy capture
of 'this' redundant with by-copy capture default" }
+ // P0409R2 - C++2A lambda capture [=, this]
+ auto k = [=, this] { return a; };// { dg-error "explicit by-copy capture
of 'this' redundant with by-copy capture default" "" { target c++17_down } }
auto l = [&, this] { return a; };
auto m = [=, *this] { return a; };// { dg-error "'*this' capture only
available with" "" { target c++14_down } }
auto n = [&, *this] { return a; };// { dg-error "'*this' capture only
available with" "" { target c++14_down } }
auto o = [*this, &v] { return a + v; };// { dg-error "'*this' capture only
available with" "" { target c++14_down } }
auto p = [*this] { this = 0; }; // { dg-error "lvalue required as left
operand of assignment" }
// { dg-error "'*this' capture only
available with" "" { target c++14_down } .-1 }
+ auto q = [=, this, *this] { return a; };// { dg-error "already captured
'this'" }
+ // { dg-error "'*this' capture only
available with" "" { target c++14_down } .-1 }
+ // { dg-error "explicit by-copy
capture of 'this' redundant with by-copy capture default" "" { target
c++17_down } .-2 }
+ auto r = [=, this, this] { return a; };// { dg-error "already captured
'this'" }
+ // { dg-error "explicit by-copy
capture of 'this' redundant with by-copy capture default" "" { target
c++17_down } .-1 }
+ auto s = [=, *this, this] { return a; };// { dg-error "already captured
'this'" }
+ // { dg-error "'*this' capture only
available with" "" { target c++14_down } .-1 }
+ // { dg-error "explicit by-copy
capture of 'this' redundant with by-copy capture default" "" { target
c++17_down } .-2 }
+ auto t = [=, *this, *this] { return a; };// { dg-error "already captured
'this'" }
+ // { dg-error "'*this' capture
only available with" "" { target c++14_down } .-1 }
+ auto u = [&, this, *this] { return a; };// { dg-error "already captured
'this'" }
+ // { dg-error "'*this' capture only
available with" "" { target c++14_down } .-1 }
+ auto w = [&, this, this] { return a; };// { dg-error "already captured
'this'" }
+ auto x = [&, *this, this] { return a; };// { dg-error "already captured
'this'" }
+ // { dg-error "'*this' capture only
available with" "" { target c++14_down } .-1 }
+ auto y = [&, *this, *this] { return a; };// { dg-error "already captured
'this'" }
+ // { dg-error "'*this' capture
only available with" "" { target c++14_down } .-1 }
}
};
struct B {
--- gcc/testsuite/g++.dg/cpp0x/lambda/lambda-capture-redundancy.C.jj
2014-03-10 10:50:00.000000000 +0100
+++ gcc/testsuite/g++.dg/cpp0x/lambda/lambda-capture-redundancy.C
2017-09-20 10:40:43.608253519 +0200
@@ -7,7 +7,7 @@ void S2::f(int i) {
[&, i]{ }; // OK
[&, &i]{ }; // { dg-error "" } i preceded by & when & is the default
[=, i]{ }; // { dg-error "" } i not preceded by & when = is the default
- [=, this]{ }; // { dg-error "" } this when = is the default
+ [=, this]{ }; // { dg-error "" "" { target c++17_down } } this
when = is the default
[i, i]{ }; // { dg-error "" } i repeated
[this, this]{ }; // { dg-error "" } i repeated
}
Jakub
