[clang] [analyzer] Untangle subcheckers of CStringChecker (PR #186802)

[Donát Nagy via cfe-commits]

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@@ -779,7 +787,10 @@ ProgramStateRef CStringChecker::CheckOverlap(CheckerContext &C,
 }
 
 void CStringChecker::emitOverlapBug(CheckerContext &C, ProgramStateRef state,
-                                  const Stmt *First, const Stmt *Second) const {
+                                    const Stmt *First,
+                                    const Stmt *Second) const {
+  assert(BufferOverlap.isEnabled() &&
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NagyDonat wrote:

Okay for now. However, eventually the return value at the call site should not depend on this (when this sub-checker is moved out of alpha), so perhaps then we can unify the assert and the check.

https://github.com/llvm/llvm-project/pull/186802