Regarding stripping and -g

[bearophile]

I have compiled a small D program with LDC2 on Windows32, with 
and without -g and I have stripped it. Here are the resulting 
binary sizes:

2.166.124 test.exe  (1)
4.421.713 test_g.exe (2)
   853.518 test_stripped.exe (3)
1.204.750 test_g_stripped.exe (4)

What's the difference between the stripped (3) and the stripped 
program compiled with -g (4)?

Is it a good idea to make ldmd2 also strip the exe binary if the 
-g switch is not used?

Bye,
bearophile