_Ios_Openmode is an implementation detail of the GNU c++ stdlib whereas
ios_base::openmode is the portable way to go
--- a/libsidplay/src/sidtune/SidTune.cpp
+++ b/libsidplay/src/sidtune/SidTune.cpp
@@ -29,6 +29,7 @@
 #   include <new>
 #endif
 #include <iostream>
+#include <ios>
 #include <iomanip>
 #include <string.h>
 #include <limits.h>
@@ -283,7 +284,7 @@ bool SidTune::loadFile(const char* fileName, Buffer_sidtt<const uint_least8_t>&
     uint_least32_t fileLen = 0;
 
     // This sucks big time
-    std::_Ios_Openmode createAtrr = std::ios::in;
+    std::ios_base::openmode createAtrr = std::ios::in;
 #ifdef HAVE_IOS_NOCREATE
     createAtrr |= std::ios::nocreate;
 #endif
@@ -952,7 +953,7 @@ bool SidTune::saveC64dataFile( const char* fileName, bool overWriteFlag )
     if ( status )
     {
         // Open binary output file stream.
-        std::_Ios_Openmode createAttr = std::ios::out;
+        std::ios_base::openmode createAttr = std::ios::out;
 #if defined(HAVE_IOS_BIN)
         createAttr |= std::ios::bin;
 #else
@@ -1002,7 +1003,7 @@ bool SidTune::saveSIDfile( const char* fileName, bool overWriteFlag )
     if ( status )
     {
         // Open ASCII output file stream.
-        std::_Ios_Openmode createAttr = std::ios::out;
+        std::ios_base::openmode createAttr = std::ios::out;
         if ( overWriteFlag )
             createAttr |= std::ios::trunc;
         else
@@ -1036,7 +1037,7 @@ bool SidTune::savePSIDfile( const char* fileName, bool overWriteFlag )
     if ( status )
     {
         // Open binary output file stream.
-        std::_Ios_Openmode createAttr = std::ios::out;
+        std::ios_base::openmode createAttr = std::ios::out;
 #if defined(HAVE_IOS_BIN)
         createAttr |= std::ios::bin;
 #else