libstdc++: Move stacktrace tests to 19_diagnostics directory

This matches where the feature is defined in the current draft.

libstdc++-v3/ChangeLog:

	* testsuite/20_util/stacktrace/entry.cc: Moved to...
	* testsuite/19_diagnostics/stacktrace/entry.cc: ...here.
	* testsuite/20_util/stacktrace/synopsis.cc: Moved to...
	* testsuite/19_diagnostics/stacktrace/synopsis.cc: ...here.
	* testsuite/20_util/stacktrace/version.cc: Moved to...
	* testsuite/19_diagnostics/stacktrace/version.cc: ...here.

3 files changed, 110 insertions, 0 deletions

diff --git a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/entry.cc b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/entry.cc
new file mode 100644
index 0000000..0bbcabd
--- /dev/null
+++ b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/entry.cc
@@ -0,0 +1,53 @@
+// { dg-options "-std=gnu++23 -lstdc++_libbacktrace" }
+// { dg-do run { target c++23 } }
+// { dg-require-effective-target stacktrace }
+
+#include <stacktrace>
+#include "testsuite_hooks.h"
+
+static_assert( std::regular<std::stacktrace_entry> );
+static_assert( std::three_way_comparable<std::stacktrace_entry> );
+
+constexpr bool
+test_constexpr()
+{
+  std::stacktrace_entry empty;
+  VERIFY( !empty );
+  VERIFY( empty == empty );
+  VERIFY( std::is_eq(empty <=> empty) );
+
+  std::stacktrace_entry::native_handle_type native  = empty.native_handle();
+  VERIFY( empty.native_handle() == native );
+
+  return true;
+}
+static_assert( test_constexpr() );
+
+void
+test_members()
+{
+  std::stacktrace_entry empty;
+  VERIFY( empty.description().size() == 0 );
+  VERIFY( empty.source_file().size() == 0 );
+  VERIFY( empty.source_line() == 0 );
+
+  std::stacktrace_entry e1 = std::stacktrace::current().at(0);
+  std::stacktrace_entry e2 = std::stacktrace::current().at(0);
+  VERIFY( e1 != e2 );
+  VERIFY( e1.description() == e2.description() );
+  VERIFY( e1.source_file() == e2.source_file() );
+  VERIFY( e1.source_line() != e2.source_line() );
+
+  std::stacktrace_entry e3 = []{
+    return std::stacktrace::current().at(0);
+  }();
+  VERIFY( e1 != e3 );
+  VERIFY( e1.description() != e3.description() );
+  VERIFY( e1.source_file() == e3.source_file() );
+  VERIFY( e1.source_line() != e3.source_line() );
+}
+
+int main()
+{
+  test_constexpr();
+}
diff --git a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/synopsis.cc b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/synopsis.cc
new file mode 100644
index 0000000..72582fa
--- /dev/null
+++ b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/synopsis.cc
@@ -0,0 +1,46 @@
+// { dg-options "-std=gnu++23" }
+// { dg-do compile { target c++23 } }
+// { dg-require-effective-target stacktrace }
+
+#include <stacktrace>
+
+#ifndef __cpp_lib_stacktrace
+# error "Feature-test macro for stacktrace missing in <stacktrace>"
+#elif __cpp_lib_stacktrace < 202011L
+# error "Feature-test macro for stacktrace has wrong value in <stacktrace>"
+#endif
+
+namespace std
+{
+  class stacktrace_entry;
+
+  template<class Allocator>
+    class basic_stacktrace;
+
+  using stacktrace = basic_stacktrace<allocator<stacktrace_entry>>;
+
+  template<class Allocator>
+    void swap(basic_stacktrace<Allocator>& a, basic_stacktrace<Allocator>& b)
+    noexcept(noexcept(a.swap(b)));
+
+  string to_string(const stacktrace_entry& f);
+
+  template<class Allocator>
+    string to_string(const basic_stacktrace<Allocator>& st);
+
+  template<class charT, class traits>
+    basic_ostream<charT, traits>&
+    operator<<(basic_ostream<charT, traits>& os, const stacktrace_entry& f);
+
+  template<class charT, class traits, class Allocator>
+    basic_ostream<charT, traits>&
+    operator<<(basic_ostream<charT, traits>& os, const basic_stacktrace<Allocator>& st);
+
+  namespace pmr {
+    using stacktrace = basic_stacktrace<polymorphic_allocator<stacktrace_entry>>;
+  }
+
+  template<class T> struct hash;
+  template<> struct hash<stacktrace_entry>;
+  template<class Allocator> struct hash<basic_stacktrace<Allocator>>;
+}
diff --git a/libstdc++-v3/testsuite/19_diagnostics/stacktrace/version.cc b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/version.cc
new file mode 100644
index 0000000..ed466be
--- /dev/null
+++ b/libstdc++-v3/testsuite/19_diagnostics/stacktrace/version.cc
@@ -0,0 +1,11 @@
+// { dg-options "-std=gnu++23" }
+// { dg-do preprocess { target c++23 } }
+// { dg-require-effective-target stacktrace }
+
+#include <version>
+
+#ifndef __cpp_lib_stacktrace
+# error "Feature-test macro for stacktrace missing in <version>"
+#elif __cpp_lib_stacktrace < 202011L
+# error "Feature-test macro for stacktrace has wrong value in <version>"
+#endif