[analyzer][NFC] Cleanup BugType lazy-init patterns (#76655)

Cleanup most of the lazy-init `BugType` legacy.
Some will be preserved, as those are slightly more complicated to
refactor.

Notice, that the default category for `BugType` is `LogicError`. I
omitted setting this explicitly where I could.

Please, actually have a look at the diff. I did this manually, and we
rarely check the bug type descriptions and stuff in tests, so the
testing might be shallow on this one.

1 files changed, 2 insertions, 6 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp
index 4ca49b9..6560fd2 100644
--- a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp
@@ -823,7 +823,7 @@ class StdLibraryFunctionsChecker
   using FunctionSummaryMapType = llvm::DenseMap<const FunctionDecl *, Summary>;
   mutable FunctionSummaryMapType FunctionSummaryMap;
 
-  mutable std::unique_ptr<BugType> BT_InvalidArg;
+  const BugType BT_InvalidArg{this, "Function call with invalid argument"};
   mutable bool SummariesInitialized = false;
 
   static SVal getArgSVal(const CallEvent &Call, ArgNo ArgN) {
@@ -875,11 +875,7 @@ private:
     VC->describe(ValueConstraint::Violation, Call, C.getState(), Summary,
                  MsgOs);
     Msg[0] = toupper(Msg[0]);
-    if (!BT_InvalidArg)
-      BT_InvalidArg = std::make_unique<BugType>(
-          CheckName, "Function call with invalid argument",
-          categories::LogicError);
-    auto R = std::make_unique<PathSensitiveBugReport>(*BT_InvalidArg, Msg, N);
+    auto R = std::make_unique<PathSensitiveBugReport>(BT_InvalidArg, Msg, N);
 
     for (ArgNo ArgN : VC->getArgsToTrack()) {
       bugreporter::trackExpressionValue(N, Call.getArgExpr(ArgN), *R);