[clang] [analyzer] Untangle subcheckers of CStringChecker (PR #113312)

[via cfe-commits]

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@@ -768,9 +776,17 @@ ProgramStateRef CStringChecker::CheckOverlap(CheckerContext &C,
   std::tie(stateTrue, stateFalse) = state->assume(*OverlapTest);
 
   if (stateTrue && !stateFalse) {
-    // Overlap!
-    emitOverlapBug(C, stateTrue, First.Expression, Second.Expression);
-    return nullptr;
+    if (Filter.CheckCStringBufferOverlap) {
+      // Overlap!
+      emitOverlapBug(C, stateTrue, First.Expression, Second.Expression);
+      return nullptr;
+    }
+    // FIXME: We detected a fatal error here, we should stop analysis even if we
+    // chose not to emit a report here. However, as long as our overlap checker
+    // is in alpha, lets just pretend nothing happened.
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isuckatcs wrote:

Nit: same as in case of the copies of this section. 


https://github.com/llvm/llvm-project/pull/113312