libstdc++: Fix some warnings in filesystem tests

There's a -Wunused-but-set-variable warning in operations/all.cc which
can be fixed with [[maybe_unused]].

The statements in operations/copy.cc give -Wunused-value warnings. I
think I meant to use |= rather than !=.

And operations/file_size.cc gets -Wsign-compare warnings.

	* testsuite/27_io/filesystem/operations/all.cc: Mark unused variable.
	* testsuite/27_io/filesystem/operations/copy.cc: Fix typo.
	* testsuite/experimental/filesystem/operations/copy.cc: Likewise.
	* testsuite/27_io/filesystem/operations/file_size.cc: Use correct type
	for return value, and in comparison.
	* testsuite/experimental/filesystem/operations/file_size.cc: Likewise.

libstdc++-v3/ChangeLog

 2020-03-05  Jonathan Wakely  <jwakely@redhat.com>
 
+	* testsuite/27_io/filesystem/operations/all.cc: Mark unused variable.
+	* testsuite/27_io/filesystem/operations/copy.cc: Fix typo.
+	* testsuite/experimental/filesystem/operations/copy.cc: Likewise.
+	* testsuite/27_io/filesystem/operations/file_size.cc: Use correct type
+	for return value, and in comparison.
+	* testsuite/experimental/filesystem/operations/file_size.cc: Likewise.
+
 	PR libstdc++/94051
 	* include/std/string_view: Include <bits/ostream_insert.h>.
 	* testsuite/21_strings/basic_string_view/inserters/94051.cc: New test.

libstdc++-v3/testsuite/27_io/filesystem/operations/all.cc

@@ -39,7 +39,7 @@ main()
   const std::filesystem::perm_options permopts{};
   std::filesystem::space_info sp;
   std::error_code ec;
-  bool b;
+  bool b [[maybe_unused]];
   std::uintmax_t size;
 
   std::filesystem::absolute(p);

libstdc++-v3/testsuite/27_io/filesystem/operations/copy.cc

@@ -57,7 +57,7 @@ test01()
   VERIFY( !exists(to) );
 
   ec.clear();
-  opts != fs::copy_options::recursive;
+  opts |= fs::copy_options::recursive;
   fs::copy("/", to, opts, ec);
   VERIFY( ec == std::make_error_code(std::errc::is_a_directory) );
   VERIFY( !exists(to) );

libstdc++-v3/testsuite/27_io/filesystem/operations/file_size.cc

@@ -29,9 +29,9 @@ void
 test01()
 {
   std::error_code ec;
-  size_t size = fs::file_size(".", ec);
+  auto size = fs::file_size(".", ec);
   VERIFY( ec == std::errc::is_a_directory );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 
   try {
     size = fs::file_size(".");
@@ -40,7 +40,7 @@ test01()
     ec = e.code();
   }
   VERIFY( ec == std::errc::is_a_directory );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 }
 
 void
@@ -49,9 +49,9 @@ test02()
   fs::path p = __gnu_test::nonexistent_path();
 
   std::error_code ec;
-  size_t size = fs::file_size(p, ec);
+  auto size = fs::file_size(p, ec);
   VERIFY( ec );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 
   try {
     size = fs::file_size(p);
@@ -60,7 +60,7 @@ test02()
     ec = e.code();
   }
   VERIFY( ec );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 }
 
 int

libstdc++-v3/testsuite/experimental/filesystem/operations/copy.cc

@@ -57,7 +57,7 @@ test01()
   VERIFY( !exists(to) );
 
   ec.clear();
-  opts != fs::copy_options::recursive;
+  opts |= fs::copy_options::recursive;
   fs::copy("/", to, opts, ec);
   VERIFY( ec == std::make_error_code(std::errc::is_a_directory) );
   VERIFY( !exists(to) );

libstdc++-v3/testsuite/experimental/filesystem/operations/file_size.cc

@@ -29,9 +29,9 @@ void
 test01()
 {
   std::error_code ec;
-  size_t size = fs::file_size(".", ec);
+  auto size = fs::file_size(".", ec);
   VERIFY( ec == std::errc::is_a_directory );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 
   try {
     size = fs::file_size(".");
@@ -40,7 +40,7 @@ test01()
     ec = e.code();
   }
   VERIFY( ec == std::errc::is_a_directory );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 }
 
 void
@@ -49,9 +49,9 @@ test02()
   fs::path p = __gnu_test::nonexistent_path();
 
   std::error_code ec;
-  size_t size = fs::file_size(p, ec);
+  auto size = fs::file_size(p, ec);
   VERIFY( ec );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 
   try {
     size = fs::file_size(p);
@@ -60,7 +60,7 @@ test02()
     ec = e.code();
   }
   VERIFY( ec );
-  VERIFY( size == -1 );
+  VERIFY( size == (std::uintmax_t)-1 );
 }
 
 int