[analyzer][NFCi] Use the correct BugType in CStringChecker.

[phyBrackets]

Summary

There is different bug types for different types of bugs but the emitAdditionOverflowbug seems to use bugtype BT_NotCSting but actually it have to use BT_AdditionOverflow .

[phyBrackets]

Use the git blame

[steakhal]

I would recommend not touching the unrelated lines, unless you have a clear motive. Other than that I think its fair to say that this must have been a bug. Ill check the report diff tomorrow, prior accepting this.

[phyBrackets]

In D119462#3312482, @steakhal wrote:

I would recommend not touching the unrelated lines, unless you have a clear motive. Other than that I think its fair to say that this must have been a bug. Ill check the report diff tomorrow, prior accepting this.

Yeah will keep in mind. Thanks.

[phyBrackets]

Hey @steakhal , any updates on this ? should I commit it ?

[steakhal]

I think yes, go ahead!

[phyBrackets]

In D119462#3319031, @steakhal wrote:

I think yes, go ahead!

Thanks !

clang/lib/StaticAnalyzer/Checkers/CStringChecker.cpp

public:
 
   void emitNullArgBug(CheckerContext &C, ProgramStateRef State, const Stmt *S,
                       StringRef WarningMsg) const;
   void emitOutOfBoundsBug(CheckerContext &C, ProgramStateRef State,
                           const Stmt *S, StringRef WarningMsg) const;
   void emitNotCStringBug(CheckerContext &C, ProgramStateRef State,
                          const Stmt *S, StringRef WarningMsg) const;
   void emitAdditionOverflowBug(CheckerContext &C, ProgramStateRef State) const;
-
   ProgramStateRef checkAdditionOverflow(CheckerContext &C,
                                             ProgramStateRef state,
                                             NonLoc left,
                                             NonLoc right) const;
 
   // Return true if the destination buffer of the copy function may be in bound.
   // Expects SVal of Size to be positive and unsigned.
   // Expects SVal of FirstBuf to be a FieldRegion.
ProgramStateRef CStringChecker::CheckBufferAccess(CheckerContext &C,
 
   // Check that the first buffer is sufficiently long.
   SVal BufStart =
       svalBuilder.evalCast(BufVal, PtrTy, Buffer.Expression->getType());
   if (Optional<Loc> BufLoc = BufStart.getAs<Loc>()) {
 
     SVal BufEnd =
         svalBuilder.evalBinOpLN(State, BO_Add, *BufLoc, LastOffset, PtrTy);
-
     State = CheckLocation(C, State, Buffer, BufEnd, Access);
 
     // If the buffer isn't large enough, abort.
     if (!State)
       return nullptr;
   }
 
   // Large enough or not, return this state!
if (ExplodedNode *N = C.generateNonFatalErrorNode(State)) {
     Report->addRange(S->getSourceRange());
     C.emitReport(std::move(Report));
   }
 }
 
 void CStringChecker::emitAdditionOverflowBug(CheckerContext &C,
                                              ProgramStateRef State) const {
   if (ExplodedNode *N = C.generateErrorNode(State)) {
-    if (!BT_NotCString)
-      BT_NotCString.reset(
+    if (!BT_AdditionOverflow)
+      BT_AdditionOverflow.reset(
           new BuiltinBug(Filter.CheckNameCStringOutOfBounds, "API",
                          "Sum of expressions causes overflow."));
 
     // This isn't a great error message, but this should never occur in real
     // code anyway -- you'd have to create a buffer longer than a size_t can
     // represent, which is sort of a contradiction.
     const char *WarningMsg =
         "This expression will create a string whose length is too big to "
         "be represented as a size_t";
 
-    auto Report =
-        std::make_unique<PathSensitiveBugReport>(*BT_NotCString, WarningMsg, N);
+    auto Report = std::make_unique<PathSensitiveBugReport>(*BT_AdditionOverflow,
+                                                           WarningMsg, N);
     C.emitReport(std::move(Report));
   }
 }
 
 ProgramStateRef CStringChecker::checkAdditionOverflow(CheckerContext &C,
                                                      ProgramStateRef state,
                                                      NonLoc left,
                                                      NonLoc right) const {