Please describe the problem:
We are currently trying to integrate gtkmm-widgets (Gtk::Widget - derived classes) into glade3's palette and had some success with it, even Glib::Property-Members of the class show up in glade's "Properties" window.

However, you cannot have 0 or smaller as a default value for Glib::Property<float> ot Glib::Property<double>, glade complains about the value being smaller than the default and refuses to show the property.

Digging int it, i found that 
GParamSpec* Value<float>::create_param_spec(const Glib::ustring& name)
in glib/glibmm/value_basictypes.cc defines G_MINFLOAT as the minimum value for the created param_spec.

G_MINFLOAT, however, is defined as the smallest possible float and e.g on x86 is something like 1.175494e-38.

The same applies to Value<double>::create_param_spec, respectively.

so, if create_param_spec intends to make available the whole range of values (as do the int types) we should possibly use -G_MAX_FLOAT.
I've tested this on x86, and -GMAX_FLOAT seems to be a valid float value, but I'm not so sure about other architectures, so perhaps someone with more insight into internal float representation could shed some light on it.


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Does this happen every time?


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