if(arr) now a warning

[TC via Digitalmars-d]

What about less intrusive change as a compromise?

I'm the C# guy and they solve these problems just with warnings. 
Each warning has some ID and compiler spits it out with the 
description of a problem itself.

Developers than have 4 ways to handle it:
1) ignore it and live with the warning
2) change the code to be correct
3) disable this exact warning type for a whole project
4) disable this exact warning in source file at the place of the 
warning itself

I think that similar approach would be helpful here.
Say we have an Andrei's allocator code which he knows that is 
correct. But spits out a lot of false positive warnings. So at 
the module header he just adds something like:

pragma(disablewarn, 123);

and don't care about it further.

So personally I wouldn't necessarily deprecate current behaviour 
with actual codebreak, but just spit out warning about possible 
error which can be easily taken care of and still can be pretty 
useful to find possible bugs.
Actually that should be major usage for warnings - notify 
developer that something is potentially wrong.

More about C# pragmas for warning handling: 
https://msdn.microsoft.com/en-us/library/441722ys.aspx