Run Microsoft Analyzer over dmd source code

[Don]

bearophile wrote:
> Vladimir Panteleev:
> 
>> Done:  
>> http://dump.thecybershadow.net/b1e4cb6ef0a8d3c5f54d5cb09ddd1a9e/DMD.log
> 
> There are only 10 NULL deference warnings left:
> 
> s2ir.c(1043): warning C6011: Dereferencing NULL pointer 'pu++'
false (only if malloc fails)
> s2ir.c(980): warning C6011: Dereferencing NULL pointer 'cases'
false
> statement.c(3666): warning C6011: Dereferencing NULL pointer 'tbret'
clang complained about this too, might be correct.
> template.c(5353): warning C6011: Dereferencing NULL pointer 'sds'
false
> todt.c(536): warning C6011: Dereferencing NULL pointer 'type'
false
> todt.c(746): warning C6011: Dereferencing NULL pointer 'var'
false
But there's a NULL dereference in todt(59) which it missed (bug 3863).
> module.c(793): warning C6011: Dereferencing NULL pointer 'sc'
HIT! That looks real.
> mtype.c(4887): warning C6011: Dereferencing NULL pointer 'fparam->type'
maybe
> mtype.c(8130): warning C6011: Dereferencing NULL pointer 'arg->type'
maybe.
> root\root.c(1498): warning C6011: Dereferencing NULL pointer 'f->touchtime'
maybe.