What's wrong with my debugger?

Rainer Schuetze via Digitalmars-d-learn digitalmars-d-learn at puremagic.com
Thu Dec 24 01:30:24 PST 2015

On 24.12.2015 03:14, Chris wrote:
> Please see the linked screenshot: http://i.imgur.com/SpkXu5m.png
> As you can see, the inside, outside and collision arrays don't seem to
> work with the debugger. They show a bogus lenght and a bogus memory
> address. Extracting the lenghts to separate variables outl, insl and
> coll show that the arrays actually behave properly, though.
> Is that a debugger bug? Or maybe something I can fix? Thanks in advance.
> DMD 2.069.2, Mago debugger, VisualD 3.43, compiling for 32 bits if that
> makes a difference (can't get either 64 bit compilation or LDC to work)

One possible issue is that there are multiple variable declarations in 
the function with the names "outside, inside and collision". Dmd does 
not emit proper scope information for variables, so all variables show 
up anywhere in a function. (See for example 

In the locals window, mago displays all instances of variables, but with 
the same value (which might be some uninitialized value of a different 
declaration than expected). The Visual Studio debug engine shows 
different values, though.

More information about the Digitalmars-d-learn mailing list