Re: TreeStore behavior with -malign-double

[Murray Cumming <murrayc murrayc com>]

On Tue, 2006-07-11 at 15:02 -0500, Bryan Silverthorn wrote:
> I've attached a small test case (TreeViewTest.cc) that breaks when 
> compiled with -malign-double, using gtkmm-2.4.11 and 2.8.8 under RHEL 
> and FC5 respectively on i386:
> 
> "
> $ g++ TreeViewTest.cc `pkg-config --cflags --libs gtkmm-2.4` -o TreeViewTest
> $ ./TreeViewTest
> hidden data is stored correctly.
> 
> $ g++ -malign-double TreeViewTest.cc `pkg-config --cflags --libs 
> gtkmm-2.4` -o TreeViewTest
> $ ./TreeViewTest
> hidden data has gone missing!
> "
> 
> To summarize: TreeStore columns with custom data types do not correctly 
> store their values. I'm assuming that gtk+ and gtkmm were not compiled 
> with -malign-double, and that the problem is therefore a direct result 
> of the binary compatibility issues introduced by -malign-double.

That sounds very likely. In general you need to be very careful when
using compiler options. What's the purpose of this one for you?

> So this issue is probably more of a (potentially quite time-wasting) 
> gotcha than a bug per se, but it would be nice if it wasn't an issue at 
> all---or was at least documented and/or checked for at either compile or 
> run time.


-- 
Murray Cumming
murrayc murrayc com
www.murrayc.com
www.openismus.com