ZynAddSubFX: workaround for bug in Win64 GCC

When building LMMS with recent stable versions of GCC it generates
wrong code for the implicit REALTYPE specialization of the template
method stringFrom<T>() (problem in std::stringstream implementation).
By writing a custom template specialization which uses sprintf() the
bug can be circumvented.

plugins/zynaddsubfx/src/Misc/Util.h

@@ -54,6 +54,15 @@ std::string stringFrom(T x)
     return ss.str();
 }
 
+template<class T>
+std::string stringFrom(REALTYPE x)
+{
+    char buf[64];
+    sprintf( buf, "%f", x );
+    return buf;
+}
+
+
 template<class T>
 T stringTo(const char *x)
 {