[analyzer] Suppress nullability warning for _Nonnull locals zero-initialized by ObjC ARC.
Prevent the analyzer from warning when a _Nonnnull local variable is implicitly
zero-initialized because of Objective-C automated reference counting. This avoids false
positives in cases where a _Nonnull local variable cannot be initialized with an
initialization expression, such as:
NSString * _Nonnull s; // no-warning
@autoreleasepool {
s = ...;
}
The nullability checker will still warn when a _Nonnull local variable is explicitly
initialized with nil.
This suppression introduces the potential for false negatives if the local variable
is used before it is assigned a _Nonnull value. Based on a discussion with Anna Zaks,
Jordan Rose, and John McCall, I've added a FIXME to treat implicitly zero-initialized
_Nonnull locals as uninitialized in Sema's UninitializedValues analysis to avoid these
false negatives.
rdar://problem/
23522311
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@256603
91177308-0d34-0410-b5e6-
96231b3b80d8