Make VS2012 not hide .NET 4.0 bugs when targeting .NET 4.0
Since .NET 4.5 will overwrite .NET 4.0 assemblies and because you can’t deploy .NET 4.5 on Windows XP and Windows Server 2003 there is a chance that I will not be aware of bugs existing in .NET 4.0 which are fixed in .NET 4.5.
If I target the 4.0 version, bugs may be hidden from me because they are not present in .NET 4.5 which assemblies are used when debugging in VS2012 project targeting .NET 4.0. That means I can’t use VS2012 if I target .NET 4.0 on Windows XP or Windows Server 2003 machines unless I’m prepared to live with complications of not being able to reproduce such bugs on my development machine (which I’m currently not).
It would be nice if VS2012 would use .NET 4.0 assemblies when debugging/running project targeting .NET 4.0 or if there would be some SP1/fix for .NET 4.0 that would include all bug fixes introduced with .NET 4.5.
I find that a side-by-side installation would have saved us a lot of trouble.
Vlatko Malović commented
I believe that I requested the same thing as in „Support a .NET 4.0 Service Pack on Windows XP Supporting those .NET 4.0 Bugs Fixed in .NET 4.5“ (http://visualstudio.uservoice.com/forums/121579-visual-studio/suggestions/3127346-support-a-net-4-0-service-pack-on-windows-xp-supp).
I'm switching my vote to that one since it has much more votes than mine.
Thanks the suggestion Vlatko. Is there anything in particular bugs/behavior changes that you are running into? When we detect a 4.0 app running, we do shim a lot of the behavior changes, so that 4.0 apps see the old behavior, and wondering if there is ones that we might have missed.