On Tue, 1 Feb 2022 at 22:00, Jonathan Wakely via Libstdc++
<libstd...@gcc.gnu.org> wrote:
>
> Tested powerpc64le-linux, pushed to trunk.
>
>
> The standard requires directory iterators to become equal to the end
> iterator value if they report an error. Some members functions of
> filesystem::recursive_directory_iterator fail to do that.
>
> libstdc++-v3/ChangeLog:
>
> * src/c++17/fs_dir.cc (recursive_directory_iterator::increment):
> Reset state to past-the-end iterator on error.
> (fs::recursive_directory_iterator::pop(error_code&)): Likewise.
> (fs::recursive_directory_iterator::pop()): Check _M_dirs before
> it might get reset.
> * src/filesystem/dir.cc (recursive_directory_iterator): Likewise,
> for the TS implementation.
> * testsuite/27_io/filesystem/iterators/error_reporting.cc: New test.
> * testsuite/experimental/filesystem/iterators/error_reporting.cc: New
> test.
> ---
> libstdc++-v3/src/c++17/fs_dir.cc | 12 +-
> libstdc++-v3/src/filesystem/dir.cc | 12 +-
> .../filesystem/iterators/error_reporting.cc | 135 +++++++++++++++++
> .../filesystem/iterators/error_reporting.cc | 136 ++++++++++++++++++
> 4 files changed, 291 insertions(+), 4 deletions(-)
> create mode 100644
> libstdc++-v3/testsuite/27_io/filesystem/iterators/error_reporting.cc
> create mode 100644
> libstdc++-v3/testsuite/experimental/filesystem/iterators/error_reporting.cc
>
> diff --git a/libstdc++-v3/src/c++17/fs_dir.cc
> b/libstdc++-v3/src/c++17/fs_dir.cc
> index e050304c19a..149a8b0740c 100644
> --- a/libstdc++-v3/src/c++17/fs_dir.cc
> +++ b/libstdc++-v3/src/c++17/fs_dir.cc
> @@ -311,6 +311,10 @@ fs::recursive_directory_iterator::increment(error_code&
> ec)
> return *this;
> }
> }
> +
> + if (ec)
> + _M_dirs.reset();
> +
> return *this;
> }
>
> @@ -334,16 +338,20 @@ fs::recursive_directory_iterator::pop(error_code& ec)
> ec.clear();
> return;
> }
> - } while (!_M_dirs->top().advance(skip_permission_denied, ec));
> + } while (!_M_dirs->top().advance(skip_permission_denied, ec) && !ec);
> +
> + if (ec)
> + _M_dirs.reset();
> }
>
> void
> fs::recursive_directory_iterator::pop()
> {
> + const bool dereferenceable = _M_dirs != nullptr;
> error_code ec;
> pop(ec);
> if (ec)
> - _GLIBCXX_THROW_OR_ABORT(filesystem_error(_M_dirs
> + _GLIBCXX_THROW_OR_ABORT(filesystem_error(dereferenceable
> ? "recursive directory iterator cannot pop"
> : "non-dereferenceable recursive directory iterator cannot pop",
> ec));
This gives -Wunused warnings when libstdc++ is built with exceptions disabled.
Fixed by the attached, pushed to trunk.
commit 2905e1af94519b7ba3c43a57af8a7d5e10815950
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Wed Feb 2 11:40:28 2022
libstdc++: Fix -Wunused-variable warning for -fno-exceptions build
If _GLIBCXX_THROW_OR_ABORT expands to just __builtin_abort() then the
bool variable used in the filesystem_error constructor is unused. Mark
it as maybe_unused to there's no warning for -fno-exceptions builds.
libstdc++-v3/ChangeLog:
* src/c++17/fs_dir.cc (fs::recursive_directory_iterator::pop):
Add [[maybe_unused]] attribute.
* src/filesystem/dir.cc (fs::recursive_directory_iterator::pop):
Likewise.
diff --git a/libstdc++-v3/src/c++17/fs_dir.cc b/libstdc++-v3/src/c++17/fs_dir.cc
index 149a8b0740c..a77aabb6dcc 100644
--- a/libstdc++-v3/src/c++17/fs_dir.cc
+++ b/libstdc++-v3/src/c++17/fs_dir.cc
@@ -347,7 +347,7 @@ fs::recursive_directory_iterator::pop(error_code& ec)
void
fs::recursive_directory_iterator::pop()
{
- const bool dereferenceable = _M_dirs != nullptr;
+ [[maybe_unused]] const bool dereferenceable = _M_dirs != nullptr;
error_code ec;
pop(ec);
if (ec)
diff --git a/libstdc++-v3/src/filesystem/dir.cc
b/libstdc++-v3/src/filesystem/dir.cc
index ac9e70da516..7cf8e62b5e6 100644
--- a/libstdc++-v3/src/filesystem/dir.cc
+++ b/libstdc++-v3/src/filesystem/dir.cc
@@ -334,7 +334,7 @@ fs::recursive_directory_iterator::pop(error_code& ec)
void
fs::recursive_directory_iterator::pop()
{
- const bool dereferenceable = _M_dirs != nullptr;
+ [[maybe_unused]] const bool dereferenceable = _M_dirs != nullptr;
error_code ec;
pop(ec);
if (ec)
