libstdc++: One more change for Clang to support constexpr std::string [PR103295]

All writes into the allocated buffer need to be via traits_type::assign
to begin lifetimes.

libstdc++-v3/ChangeLog:

	PR libstdc++/103295
	* include/bits/basic_string.tcc (_M_construct): Use the
	traits assign member to write into allcoated memory.

diff --git a/libstdc++-v3/include/bits/basic_string.tcc b/libstdc++-v3/include/bits/basic_string.tcc
index 374406c..6f619a0 100644 (file)
--- a/libstdc++-v3/include/bits/basic_string.tcc
+++ b/libstdc++-v3/include/bits/basic_string.tcc
@@ -201,7 +201,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
                _M_data(__another);
                _M_capacity(__capacity);
              }
-           _M_data()[__len++] = *__beg;
+           traits_type::assign(_M_data()[__len++], *__beg);
            ++__beg;
          }