[clang] [clang][analyzer] CallAndMessage warnings at pointer to uninitialized struct (PR #164600)

[Donát Nagy via cfe-commits]

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@@ -179,6 +179,12 @@ def CallAndMessageChecker
                "Check whether the reciever in the message expression is "
                "undefined",
                "true", Released>,
+           CmdLineOption<
+               Boolean, "ArgPointeeInitializednessComplete",
+               "If set to true, treat a struct as initialized when all of its "
+               "members are initialized, otherwise when it has any initialized "
+               "member (used only at ArgPointeeInitializedness)",
+               "false", Released>,
----------------
NagyDonat wrote:

> Oh my god. I just realised that all of these option names are horrible. 

Yes, they are all horrible. Moreover, these options act like sub-checkers in a checker family (they enable reporting different kinds of problems), but they were implemented as options before the sub-checker pattern appeared and they were preserved for the sake of stability. I hope that eventually we can turn `CallAndMessage` into a checker family that consists of five or so checkers with clear names. @steakhal What do you think about this?

https://github.com/llvm/llvm-project/pull/164600