Mark call to sort() as error, per Alexandre Oliva.

From-SVN: r20157

gcc/testsuite/g++.old-deja/g++.robertl/eb42.C

+#include <vector.h>
+#include <algo.h>
+
+template <class T> class Expr
+{
+public :
+Expr(){};
+Expr(const T&){};
+};
+
+template <class T >
+inline bool compare(const Expr<T> a, const Expr<T> b){ return true; };
+
+int main()
+{
+vector<int>     a(3);
+sort( a.begin(), a.end(), compare ); // ERROR - no matching function 
+}