libstdc++: Remove dg-options "-std=gnu++20" from 27_io tests

The testsuite will automatically select C++20 for these tests now, and
removing the hardcoded -std option allows them to be tested for C++23
and C++26 as well.

libstdc++-v3/ChangeLog:

	* testsuite/27_io/basic_istream/extractors_character/char/lwg2499.cc:
	Remove dg-options -std=gnu++2a.
	* testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc:
	Likewise.
	* testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499.cc:
	Likewise.
	* testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc:
	Likewise.
	* testsuite/27_io/basic_istringstream/cons/char/1.cc: Likewise.
	* testsuite/27_io/basic_istringstream/cons/wchar_t/1.cc:
	Likewise.
	* testsuite/27_io/basic_istringstream/str/char/2.cc: Likewise.
	* testsuite/27_io/basic_istringstream/str/wchar_t/2.cc:
	Likewise.
	* testsuite/27_io/basic_istringstream/view/char/1.cc: Likewise.
	* testsuite/27_io/basic_istringstream/view/wchar_t/1.cc:
	Likewise.
	* testsuite/27_io/basic_ostream/emit/1.cc: Likewise.
	* testsuite/27_io/basic_ostream/inserters_character/char/deleted.cc:
	Likewise.
	* testsuite/27_io/basic_ostream/inserters_character/wchar_t/deleted.cc:
	Likewise.
	* testsuite/27_io/basic_ostringstream/cons/char/1.cc: Likewise.
	* testsuite/27_io/basic_ostringstream/cons/wchar_t/1.cc:
	Likewise.
	* testsuite/27_io/basic_ostringstream/str/char/3.cc: Likewise.
	* testsuite/27_io/basic_ostringstream/str/wchar_t/3.cc:
	Likewise.
	* testsuite/27_io/basic_ostringstream/view/char/1.cc: Likewise.
	* testsuite/27_io/basic_ostringstream/view/wchar_t/1.cc:
	Likewise.
	* testsuite/27_io/basic_stringbuf/cons/char/2.cc: Likewise.
	* testsuite/27_io/basic_stringbuf/cons/wchar_t/2.cc: Likewise.
	* testsuite/27_io/basic_stringbuf/str/char/4.cc: Likewise.
	* testsuite/27_io/basic_stringbuf/str/wchar_t/4.cc: Likewise.
	* testsuite/27_io/basic_stringbuf/view/char/1.cc: Likewise.
	* testsuite/27_io/basic_stringbuf/view/wchar_t/1.cc: Likewise.
	* testsuite/27_io/basic_stringstream/cons/char/1.cc: Likewise.
	* testsuite/27_io/basic_stringstream/cons/char/97719.cc:
	Likewise.
	* testsuite/27_io/basic_stringstream/cons/wchar_t/1.cc:
	Likewise.
	* testsuite/27_io/basic_stringstream/str/char/5.cc: Likewise.
	* testsuite/27_io/basic_stringstream/str/wchar_t/5.cc.cc:
	Likewise.
	* testsuite/27_io/basic_stringstream/view/char/1.cc: Likewise.
	* testsuite/27_io/basic_stringstream/view/wchar_t/1.cc:
	Likewise.
	* testsuite/27_io/basic_syncbuf/1.cc: Likewise.
	* testsuite/27_io/basic_syncbuf/2.cc: Likewise.
	* testsuite/27_io/basic_syncbuf/basic_ops/1.cc: Likewise.
	* testsuite/27_io/basic_syncbuf/requirements/types.cc: Likewise.
	* testsuite/27_io/basic_syncbuf/sync_ops/1.cc: Likewise.
	* testsuite/27_io/basic_syncstream/1.cc: Likewise.
	* testsuite/27_io/basic_syncstream/2.cc: Likewise.
	* testsuite/27_io/basic_syncstream/basic_ops/1.cc: Likewise.
	* testsuite/27_io/basic_syncstream/requirements/types.cc:
	Likewise.
	* testsuite/27_io/filesystem/iterators/106201.cc: Likewise.
	* testsuite/27_io/filesystem/iterators/lwg3719.cc: Likewise.
	* testsuite/27_io/filesystem/path/factory/u8path-depr.cc:
	Likewise.
	* testsuite/27_io/filesystem/path/nonmember/cmp_c++20.cc:
	Likewise.

45 files changed, 42 insertions, 87 deletions

diff --git a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499.cc b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499.cc
index 75ec75b..060cb93 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 // LWG 2499
 // operator>>(basic_istream&, CharT*) makes it hard to avoid buffer overflows
diff --git a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc
index a214365..02b0e9a 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 
 // LWG 2499
 // operator>>(basic_istream&, CharT*) makes it hard to avoid buffer overflows
diff --git a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499.cc b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499.cc
index 62689b3..9605a4f 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 // LWG 2499
 // operator>>(basic_istream&, CharT*) makes it hard to avoid buffer overflows
diff --git a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc
index dae4935..3e808aa 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 
 // LWG 2499
 // operator>>(basic_istream&, CharT*) makes it hard to avoid buffer overflows
diff --git a/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/char/1.cc
index e5b141d..923eaa0 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/char/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/char/1.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.3.2  basic_istringstream constructors  [istringstream.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/wchar_t/1.cc
index 771e149..f75afcc1 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/wchar_t/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istringstream/cons/wchar_t/1.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.3.2  basic_istringstream constructors  [istringstream.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_istringstream/str/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_istringstream/str/char/2.cc
index 9447731..641cf52 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istringstream/str/char/2.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istringstream/str/char/2.cc
@@ -17,8 +17,7 @@
 
 // 29.8.3.4  basic_istringstream member functions  [istringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_istringstream/str/wchar_t/2.cc b/libstdc++-v3/testsuite/27_io/basic_istringstream/str/wchar_t/2.cc
index 6a848f4..0d4ee36 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istringstream/str/wchar_t/2.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istringstream/str/wchar_t/2.cc
@@ -17,8 +17,7 @@
 
 // 29.8.3.4  basic_istringstream member functions  [istringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_istringstream/view/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_istringstream/view/char/1.cc
index 04aae81..781c9ab 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istringstream/view/char/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istringstream/view/char/1.cc
@@ -17,8 +17,7 @@
 
 // 29.8.3.4  basic_istringstream member functions  [istringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_istringstream/view/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_istringstream/view/wchar_t/1.cc
index 06b04b3..ed6b905 100644
--- a/libstdc++-v3/testsuite/27_io/basic_istringstream/view/wchar_t/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_istringstream/view/wchar_t/1.cc
@@ -17,8 +17,7 @@
 
 // 27.7.1.1  basic_stringbuf constructors  [lib.stringbuf.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostream/emit/1.cc b/libstdc++-v3/testsuite/27_io/basic_ostream/emit/1.cc
index a72ba45..2c2709a 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostream/emit/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostream/emit/1.cc
@@ -15,9 +15,8 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
 // { dg-additional-options "-pthread" { target pthread } }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 // { dg-require-effective-target rtti }
 
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/char/deleted.cc b/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/char/deleted.cc
index d23a3e9..73c0ab3 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/char/deleted.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/char/deleted.cc
@@ -19,8 +19,7 @@
 
 // Test character inserters defined as deleted by P1423.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 
 #include <ostream>
 
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/wchar_t/deleted.cc b/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/wchar_t/deleted.cc
index fddadeb..b3bcbb0 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/wchar_t/deleted.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostream/inserters_character/wchar_t/deleted.cc
@@ -19,8 +19,7 @@
 
 // Test wide character inserters defined as deleted by P1423.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 
 #include <ostream>
 
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/char/1.cc
index af8766f..d43472b 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/char/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/char/1.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.4.2  basic_ostringstream constructors  [ostringstream.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/wchar_t/1.cc
index 3e5eda3..7157257 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/wchar_t/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostringstream/cons/wchar_t/1.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.4.2  basic_ostringstream constructors  [ostringstream.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/char/3.cc b/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/char/3.cc
index 3dabd32..fbb77d0 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/char/3.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/char/3.cc
@@ -17,8 +17,7 @@
 
 // 29.8.4.4  basic_ostringstream member functions  [ostringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/wchar_t/3.cc b/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/wchar_t/3.cc
index 13d862b..bb1aefe 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/wchar_t/3.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostringstream/str/wchar_t/3.cc
@@ -17,8 +17,7 @@
 
 // 29.8.4.4  basic_ostringstream member functions  [ostringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/char/1.cc
index 4127908..ab938a7 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/char/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/char/1.cc
@@ -17,8 +17,7 @@
 
 // 29.8.4.4  basic_ostringstream member functions  [ostringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/wchar_t/1.cc
index 2f177d4..bc5f9ab 100644
--- a/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/wchar_t/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_ostringstream/view/wchar_t/1.cc
@@ -17,8 +17,7 @@
 
 // 29.8.4.4  basic_ostringstream member functions  [ostringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/char/2.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/char/2.cc
index 28c0e2c..bfc2ee2 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/char/2.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/char/2.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.2.2  basic_stringbuf constructors  [stringbuf.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/wchar_t/2.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/wchar_t/2.cc
index cbe9360..0c7352c 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/wchar_t/2.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/cons/wchar_t/2.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.2.2  basic_stringbuf constructors  [stringbuf.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/char/4.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/char/4.cc
index efa0cc7..b2dc2a3 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/char/4.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/char/4.cc
@@ -17,8 +17,7 @@
 
 // 29.8.2.4  basic_stringbuf member functions  [stringbuf.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/wchar_t/4.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/wchar_t/4.cc
index 4a002b9..349be66 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/wchar_t/4.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/str/wchar_t/4.cc
@@ -17,8 +17,7 @@
 
 // 29.8.2.4  basic_stringbuf member functions  [stringbuf.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/char/1.cc
index 138f4b1..4e58113 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/char/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/char/1.cc
@@ -17,8 +17,7 @@
 
 // 27.7.1.1  basic_stringbuf constructors  [lib.stringbuf.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/wchar_t/1.cc
index 30b8f05..a303d3b 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/wchar_t/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringbuf/view/wchar_t/1.cc
@@ -17,8 +17,7 @@
 
 // 27.7.1.1  basic_stringbuf constructors  [lib.stringbuf.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/1.cc
index 9eff397..abbad36 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/1.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.5.2  basic_stringstream constructors  [stringstream.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/97719.cc b/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/97719.cc
index 6a65d52..ad78358 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/97719.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/char/97719.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <iterator>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/wchar_t/1.cc
index 8007b53..e1a308a 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/wchar_t/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringstream/cons/wchar_t/1.cc
@@ -17,8 +17,7 @@
 
 // C++20 29.8.5.2  basic_stringstream constructors  [stringstream.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringstream/str/char/5.cc b/libstdc++-v3/testsuite/27_io/basic_stringstream/str/char/5.cc
index e503023..812c4dd 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringstream/str/char/5.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringstream/str/char/5.cc
@@ -17,8 +17,7 @@
 
 // 29.8.5.4  basic_stringstream member functions  [stringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringstream/str/wchar_t/5.cc.cc b/libstdc++-v3/testsuite/27_io/basic_stringstream/str/wchar_t/5.cc.cc
index 370760e..109ffed 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringstream/str/wchar_t/5.cc.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringstream/str/wchar_t/5.cc.cc
@@ -17,8 +17,7 @@
 
 // 29.8.5.4  basic_stringstream member functions  [stringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringstream/view/char/1.cc b/libstdc++-v3/testsuite/27_io/basic_stringstream/view/char/1.cc
index 91d329d..c86933c 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringstream/view/char/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringstream/view/char/1.cc
@@ -17,8 +17,7 @@
 
 // 29.8.5.4  basic_stringstream member functions  [stringstream.members]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_stringstream/view/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_stringstream/view/wchar_t/1.cc
index 7af53dc..73bde02 100644
--- a/libstdc++-v3/testsuite/27_io/basic_stringstream/view/wchar_t/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_stringstream/view/wchar_t/1.cc
@@ -17,8 +17,7 @@
 
 // 27.7.1.1  basic_stringbuf constructors  [lib.stringbuf.cons]
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 #include <sstream>
 #include <string_view>
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncbuf/1.cc b/libstdc++-v3/testsuite/27_io/basic_syncbuf/1.cc
index 80ccce8..d48ad09 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncbuf/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncbuf/1.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <syncstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncbuf/2.cc b/libstdc++-v3/testsuite/27_io/basic_syncbuf/2.cc
index a58da3d..ad1ab38 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncbuf/2.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncbuf/2.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 // { dg-require-effective-target hosted }
 
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncbuf/basic_ops/1.cc b/libstdc++-v3/testsuite/27_io/basic_syncbuf/basic_ops/1.cc
index 8c1c99a..2e719b0 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncbuf/basic_ops/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncbuf/basic_ops/1.cc
@@ -15,9 +15,8 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
 // { dg-additional-options "-pthread" { target pthread } }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncbuf/requirements/types.cc b/libstdc++-v3/testsuite/27_io/basic_syncbuf/requirements/types.cc
index 355941d..9364a30 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncbuf/requirements/types.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncbuf/requirements/types.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <syncstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncbuf/sync_ops/1.cc b/libstdc++-v3/testsuite/27_io/basic_syncbuf/sync_ops/1.cc
index 753a341..2f82669 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncbuf/sync_ops/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncbuf/sync_ops/1.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 // { dg-require-gthreads "" }
 // { dg-add-options libatomic }
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncstream/1.cc b/libstdc++-v3/testsuite/27_io/basic_syncstream/1.cc
index 80ccce8..d48ad09 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncstream/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncstream/1.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <syncstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncstream/2.cc b/libstdc++-v3/testsuite/27_io/basic_syncstream/2.cc
index a58da3d..ad1ab38 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncstream/2.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncstream/2.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 // { dg-require-effective-target hosted }
 
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncstream/basic_ops/1.cc b/libstdc++-v3/testsuite/27_io/basic_syncstream/basic_ops/1.cc
index 60181a5..39c0d91 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncstream/basic_ops/1.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncstream/basic_ops/1.cc
@@ -15,9 +15,8 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
 // { dg-additional-options "-pthread" { target pthread } }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <sstream>
diff --git a/libstdc++-v3/testsuite/27_io/basic_syncstream/requirements/types.cc b/libstdc++-v3/testsuite/27_io/basic_syncstream/requirements/types.cc
index 990e6dc..92ad944 100644
--- a/libstdc++-v3/testsuite/27_io/basic_syncstream/requirements/types.cc
+++ b/libstdc++-v3/testsuite/27_io/basic_syncstream/requirements/types.cc
@@ -15,8 +15,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++2a" }
-// { dg-do compile { target c++2a } }
+// { dg-do compile { target c++20 } }
 // { dg-require-effective-target cxx11_abi }
 
 #include <syncstream>
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/iterators/106201.cc b/libstdc++-v3/testsuite/27_io/filesystem/iterators/106201.cc
index c5fefd9..4002c7a 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/iterators/106201.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/iterators/106201.cc
@@ -1,4 +1,3 @@
-// { dg-options "-std=gnu++20" }
 // { dg-do compile { target c++20 } }
 // { dg-require-filesystem-ts "" }
 
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/iterators/lwg3719.cc b/libstdc++-v3/testsuite/27_io/filesystem/iterators/lwg3719.cc
index c19cddc..9dcb0e0 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/iterators/lwg3719.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/iterators/lwg3719.cc
@@ -1,4 +1,3 @@
-// { dg-options "-std=gnu++20" }
 // { dg-do run { target c++20 } }
 // { dg-require-filesystem-ts "" }
 
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/path/factory/u8path-depr.cc b/libstdc++-v3/testsuite/27_io/filesystem/path/factory/u8path-depr.cc
index de54668..ffa5997 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/path/factory/u8path-depr.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/path/factory/u8path-depr.cc
@@ -1,4 +1,3 @@
-// { dg-options "-std=gnu++20" }
 // { dg-do compile { target c++20 } }
 
 #include <filesystem>
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/path/nonmember/cmp_c++20.cc b/libstdc++-v3/testsuite/27_io/filesystem/path/nonmember/cmp_c++20.cc
index 75bdea8..6c51059 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/path/nonmember/cmp_c++20.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/path/nonmember/cmp_c++20.cc
@@ -1,5 +1,4 @@
-// { dg-options "-std=gnu++2a" }
-// { dg-do run { target c++2a } }
+// { dg-do run { target c++20 } }
 
 // Copyright (C) 2020-2023 Free Software Foundation, Inc.
 //