[clang] [analyzer] Model strchr/strrchr/memchr/strstr/strpbrk/strchrnul (PR #207267)

[Gábor Horváth via cfe-commits]

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@@ -2617,6 +2639,54 @@ void CStringChecker::evalStrsep(CheckerContext &C,
   C.addTransition(State);
 }
 
+void CStringChecker::evalStrchrCommon(CheckerContext &C, const CallEvent &Call,
+                                      StringRef FnName,
+                                      bool CanReturnNull) const {
+  CurrentFunctionDescription = FnName;
+  ProgramStateRef State = C.getState();
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Xazax-hun wrote:

Nit: maybe some of these could be moved down, closer to their first use (and after the first early return)?

https://github.com/llvm/llvm-project/pull/207267