diff --git a/cfg/std.cfg b/cfg/std.cfg
index 09d553b66..3cf9148ec 100644
--- a/cfg/std.cfg
+++ b/cfg/std.cfg
@@ -5857,29 +5857,38 @@ The obsolete function 'gets' is called. With 'gets' you'll get a buffer overrun
       <not-uninit/>
     </arg>
   </function>
+  <!-- std::string std::ostringstream::str() const; -->
+  <!-- @todo Implement the second version when function overloading is possible: -->
+  <!--       void std::ostringstream::str(const string & s); -->
+  <function name="std::ostringstream::str">
+    <use-retval/>
+    <const/>
+    <returnValue type="std::string"/>
+    <noreturn>false</noreturn>
+  </function>
   <!-- bool good() const; -->
-  <function name="std::ios::good,std::ios_base::good,std::ostream::good,std::ofstream::good">
+  <function name="std::ios::good,std::ios_base::good,std::ostream::good,std::ofstream::good,std::ostringstream::good">
     <use-retval/>
     <const/>
     <returnValue type="bool"/>
     <noreturn>false</noreturn>
   </function>
   <!-- bool eof() const; -->
-  <function name="std::ios::eof,std::ios_base::eof,std::ostream::eof,std::ofstream::eof">
+  <function name="std::ios::eof,std::ios_base::eof,std::ostream::eof,std::ofstream::eof,std::ostringstream::eof">
     <use-retval/>
     <const/>
     <returnValue type="bool"/>
     <noreturn>false</noreturn>
   </function>
   <!-- bool fail() const; -->
-  <function name="std::ios::fail,std::ios_base::fail,std::ostream::fail,std::ofstream::fail">
+  <function name="std::ios::fail,std::ios_base::fail,std::ostream::fail,std::ofstream::fail,std::ostringstream::fail">
     <use-retval/>
     <const/>
     <returnValue type="bool"/>
     <noreturn>false</noreturn>
   </function>
   <!-- bool bad() const; -->
-  <function name="std::ios::bad,std::ios_base::bad,std::ostream::bad,std::ofstream::bad">
+  <function name="std::ios::bad,std::ios_base::bad,std::ostream::bad,std::ofstream::bad,std::ostringstream::bad">
     <use-retval/>
     <const/>
     <returnValue type="bool"/>