diff --git a/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/char/2.cc b/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/char/2.cc
index 1a0635c0cca..c5414d4975d 100644
--- a/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/char/2.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/char/2.cc
@@ -16,6 +16,7 @@
 // <http://www.gnu.org/licenses/>.
 
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 #include <iterator>
 #include <fstream>
diff --git a/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/wchar_t/2.cc b/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/wchar_t/2.cc
index 823e275da19..c2fd748cbf0 100644
--- a/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/wchar_t/2.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/advance/istreambuf_iterators/wchar_t/2.cc
@@ -16,6 +16,7 @@
 // <http://www.gnu.org/licenses/>.
 
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 #include <iterator>
 #include <fstream>
diff --git a/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/char/4.cc b/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/char/4.cc
index 67888797047..3d1c7c7595d 100644
--- a/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/char/4.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/char/4.cc
@@ -27,6 +27,7 @@
 #include <testsuite_hooks.h>
 
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 // In the occasion of libstdc++/25482
 void test01()
diff --git a/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/wchar_t/4.cc b/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/wchar_t/4.cc
index e1adccfdd21..8d380052313 100644
--- a/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/wchar_t/4.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/copy/streambuf_iterators/wchar_t/4.cc
@@ -18,6 +18,7 @@
 // <http://www.gnu.org/licenses/>.
 
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 #include <iterator>
 #include <fstream>
diff --git a/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/2.cc b/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/2.cc
index 5179d78b455..a437bedb420 100644
--- a/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/2.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/2.cc
@@ -1,5 +1,6 @@
 // { dg-do run { target c++11 } }
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 // Copyright (C) 2020-2024 Free Software Foundation, Inc.
 //
diff --git a/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/deque.cc b/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/deque.cc
index 14f58998fef..1353282f6a0 100644
--- a/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/deque.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/copy_n/istreambuf_iterator/deque.cc
@@ -1,5 +1,6 @@
 // { dg-do run { target c++11 } }
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 // Copyright (C) 2020-2024 Free Software Foundation, Inc.
 //
diff --git a/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/char/2.cc b/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/char/2.cc
index 2a33bbaac9f..7a682edff7c 100644
--- a/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/char/2.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/char/2.cc
@@ -23,6 +23,7 @@
 #include <testsuite_hooks.h>
 
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 // In the occasion of libstdc++/25482
 void test01()
diff --git a/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/wchar_t/2.cc b/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/wchar_t/2.cc
index dfe5926c18a..c3187d17639 100644
--- a/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/wchar_t/2.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/find/istreambuf_iterators/wchar_t/2.cc
@@ -18,6 +18,7 @@
 // <http://www.gnu.org/licenses/>.
 
 // { dg-require-fileio "" }
+// { dg-additional-files "istream_unformatted-1.txt" }
 
 #include <iterator>
 #include <fstream>