[analyzer] Warn when passing pointers to const but uninitialized memory.
Passing a pointer to an uninitialized memory buffer is normally okay,
but if the function is declared to take a pointer-to-const then it's
very unlikely it will be modifying the buffer. In this case the analyzer
should warn that there will likely be a read of uninitialized memory.
This doesn't check all elements of an array, only the first one.
It also doesn't yet check Objective-C methods, only C functions and
This is controlled by a new check: alpha.core.CallAndMessageUnInitRefArg.
Patch by Per Viberg!