public inbox for gcc-cvs@sourceware.org
help / color / mirror / Atom feed
* [gcc r10-10303] libstdc++: Improve std::forward static assert message
@ 2021-11-26 15:41 Jonathan Wakely
0 siblings, 0 replies; only message in thread
From: Jonathan Wakely @ 2021-11-26 15:41 UTC (permalink / raw)
To: gcc-cvs, libstdc++-cvs
https://gcc.gnu.org/g:453a8f3d3966f024fae8b8bb40f968e4be2b458e
commit r10-10303-g453a8f3d3966f024fae8b8bb40f968e4be2b458e
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Tue Sep 28 12:35:29 2021 +0100
libstdc++: Improve std::forward static assert message
The previous message told you something was wrong, but not why it
happened or why it's bad. This changes it to explain that the function
is being misused.
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
* include/bits/move.h (forward(remove_reference_t<T>&&)):
Improve text of static_assert.
* testsuite/20_util/forward/c_neg.cc: Adjust dg-error.
* testsuite/20_util/forward/f_neg.cc: Likewise.
(cherry picked from commit a11052d98db2f2a61841f0c5ee84de4ca1b3e296)
Diff:
---
libstdc++-v3/include/bits/move.h | 4 ++--
libstdc++-v3/testsuite/20_util/forward/c_neg.cc | 2 +-
libstdc++-v3/testsuite/20_util/forward/f_neg.cc | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/libstdc++-v3/include/bits/move.h b/libstdc++-v3/include/bits/move.h
index 5a4dbdc823c..b5a4020eeee 100644
--- a/libstdc++-v3/include/bits/move.h
+++ b/libstdc++-v3/include/bits/move.h
@@ -86,8 +86,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
constexpr _Tp&&
forward(typename std::remove_reference<_Tp>::type&& __t) noexcept
{
- static_assert(!std::is_lvalue_reference<_Tp>::value, "template argument"
- " substituting _Tp is an lvalue reference type");
+ static_assert(!std::is_lvalue_reference<_Tp>::value,
+ "std::forward must not be used to convert an rvalue to an lvalue");
return static_cast<_Tp&&>(__t);
}
diff --git a/libstdc++-v3/testsuite/20_util/forward/c_neg.cc b/libstdc++-v3/testsuite/20_util/forward/c_neg.cc
index 8b6736d42f0..5e318ed67f4 100644
--- a/libstdc++-v3/testsuite/20_util/forward/c_neg.cc
+++ b/libstdc++-v3/testsuite/20_util/forward/c_neg.cc
@@ -17,7 +17,7 @@
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
-// { dg-error "static assertion failed" "" { target *-*-* } 89 }
+// { dg-error "convert an rvalue to an lvalue" "" { target *-*-* } 0 }
#include <list>
diff --git a/libstdc++-v3/testsuite/20_util/forward/f_neg.cc b/libstdc++-v3/testsuite/20_util/forward/f_neg.cc
index 4b697f1cd5d..c6cf880bd15 100644
--- a/libstdc++-v3/testsuite/20_util/forward/f_neg.cc
+++ b/libstdc++-v3/testsuite/20_util/forward/f_neg.cc
@@ -17,7 +17,7 @@
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
-// { dg-error "static assertion failed" "" { target *-*-* } 89 }
+// { dg-error "convert an rvalue to an lvalue" "" { target *-*-* } 0 }
#include <utility>
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2021-11-26 15:41 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-11-26 15:41 [gcc r10-10303] libstdc++: Improve std::forward static assert message Jonathan Wakely
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).