[PATCH] libstdc++: Fix error handling for std::filesystem::equivalent [PR113250]

[Ken Matsui]

This patch made std::filesystem::equivalent correctly throw an exception
when either path does not exist as per [fs.op.equivalent]/4.

libstdc++-v3/ChangeLog:

        * src/c++17/fs_ops.cc (equivalent): Use || instead of &&.
        * testsuite/27_io/filesystem/operations/equivalent.cc: Handle
        error codes.

Signed-off-by: Ken Matsui <kmat...@gcc.gnu.org>
---
 libstdc++-v3/src/c++17/fs_ops.cc                              | 2 +-
 .../testsuite/27_io/filesystem/operations/equivalent.cc       | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/libstdc++-v3/src/c++17/fs_ops.cc b/libstdc++-v3/src/c++17/fs_ops.cc
index e0b308a37ea..61df19753ef 100644
--- a/libstdc++-v3/src/c++17/fs_ops.cc
+++ b/libstdc++-v3/src/c++17/fs_ops.cc
@@ -897,7 +897,7 @@ fs::equivalent(const path& p1, const path& p2, error_code& 
ec) noexcept
       return st1.st_dev == st2.st_dev && st1.st_ino == st2.st_ino;
 #endif
     }
-  else if (!exists(s1) && !exists(s2))
+  else if (!exists(s1) || !exists(s2))
     ec = std::make_error_code(std::errc::no_such_file_or_directory);
   else if (err)
     ec.assign(err, std::generic_category());
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/operations/equivalent.cc 
b/libstdc++-v3/testsuite/27_io/filesystem/operations/equivalent.cc
index 78f6e368204..68f32366d65 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/operations/equivalent.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/operations/equivalent.cc
@@ -34,13 +34,13 @@ test01()
   bool result;
 
   result = equivalent(p1, p2, ec);
-  VERIFY( ec );
+  VERIFY( ec == std::errc::no_such_file_or_directory );
   VERIFY( !result );
 
   __gnu_test::scoped_file f1(p1);
   ec = bad_ec;
   result = equivalent(p1, p2, ec);
-  VERIFY( !ec );
+  VERIFY( ec == std::errc::no_such_file_or_directory );
   VERIFY( !result );
 
   __gnu_test::scoped_file f2(p2);
-- 
2.43.0