Index: i686-w64-mingw32/include/c++/4.8.0/bits/stl_algo.h
===================================================================
--- i686-w64-mingw32/include/c++/4.8.0/bits/stl_algo.h	(revision 94918)
+++ i686-w64-mingw32/include/c++/4.8.0/bits/stl_algo.h	(working copy)
@@ -5214,9 +5214,21 @@
 	    _RandomAccessIterator>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      if (__first != __last)
-	for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
-	  std::iter_swap(__i, __first + (std::rand() % ((__i - __first) + 1)));
+      if (__first != __last) {
+          // Bugfix: std::rand() may provide "small" numbers only and indeed it
+          //         does when using Windows libc (x < 32768).
+          //         We initialize and use a xorshift implementation seeded by
+          //         a couple of calls to rand() instead of using rand() for all
+          //         the random numbers needed.
+          unsigned __xss = (unsigned)std::rand() ^ ((unsigned)std::rand()<<15);
+          __xss += !__xss;
+          for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i) {
+              __xss ^= __xss << 13;
+              __xss ^= __xss >> 17;
+              __xss ^= __xss << 5;
+              std::iter_swap(__i, __first + (__xss % ((__i - __first) + 1)));
+          }
+      }
     }
 
   /**
Index: i686-w64-mingw32/include/c++/4.8.0/ext/algorithm
===================================================================
--- i686-w64-mingw32/include/c++/4.8.0/ext/algorithm	(revision 94918)
+++ i686-w64-mingw32/include/c++/4.8.0/ext/algorithm	(working copy)
@@ -276,8 +276,18 @@
       _Distance __remaining = std::distance(__first, __last);
       _Distance __m = min(__n, __remaining);
 
+      // Bugfix: std::rand() may provide "small" numbers only and indeed it
+      //         does when using Windows libc (x < 32768).
+      //         We initialize and use a xorshift implementation seeded by
+      //         a couple of calls to rand() instead of using rand() for all
+      //         the random numbers needed.
+      unsigned __xss = (unsigned)std::rand() ^ ((unsigned)std::rand()<<15);
+      __xss += !__xss;
       while (__m > 0)
 	{
-	  if ((std::rand() % __remaining) < __m)
+      __xss ^= __xss << 13;
+      __xss ^= __xss >> 17;
+      __xss ^= __xss << 5;
+	  if ((__xss % __remaining) < __m)
 	    {
 	      *__out = *__first;
 	      ++__out;