[analyzer] Remove dead code in ObjCDeallocChecker that checked for a missing [super dealloc] call

[ddkilzer]

Summary

This is now handled by Sema::ActOnFinishFunctionBody() before ObjCDeallocChecker::checkASTDecl() is called.

A test added to test/Analysis to exercise this code path just prints the newer warning from Sema::ActOnFinishFunctionBody().

[jordan_rose]

Huh, I'm surprised and a bit concerned that we have no tests for this, but this seems reasonable. Thanks! Do you have commit access or do you need me to commit for you?

[ddkilzer]

I did try writing a test for this, but the diag::warn_objc_missing_super_dealloc message for the check in Sema::ActOnFinishFunctionBody() is printed instead of this one.

I do not have commit access. Please commit for me at your convenience. Thanks!

[ddkilzer]

BTW, I'm happy to write a test under tests/Analysis if you'd like, but these tests appear to cover all cases:

test/SemaObjC/warn-missing-super.m
test/SemaObjCXX/warn-missing-super.mm

[ddkilzer]

Fix patch context by uploading through arc.

[jordan_rose]

Committed in r216272.

lib/StaticAnalyzer/Checkers/CheckObjCDealloc.cpp

 #include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
 #include "clang/StaticAnalyzer/Core/Checker.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace clang;
 using namespace ento;
 
-static bool scan_dealloc(Stmt *S, Selector Dealloc) {
-
-  if (ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S))
-    if (ME->getSelector() == Dealloc) {
-      switch (ME->getReceiverKind()) {
-      case ObjCMessageExpr::Instance: return false;
-      case ObjCMessageExpr::SuperInstance: return true;
-      case ObjCMessageExpr::Class: break;
-      case ObjCMessageExpr::SuperClass: break;
-      }
-    }
-
-  // Recurse to children.
-
-  for (Stmt::child_iterator I = S->child_begin(), E= S->child_end(); I!=E; ++I)
-    if (*I && scan_dealloc(*I, Dealloc))
-      return true;
-
-  return false;
-}
-
 static bool scan_ivar_release(Stmt *S, ObjCIvarDecl *ID,
                               const ObjCPropertyDecl *PD,
                               Selector Release,
                               IdentifierInfo* SelfII,
                               ASTContext &Ctx) {
 
   // [mMyIvar release]
   if (ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S))
if (!MD) { // No dealloc found.
     llvm::raw_string_ostream os(buf);
     os << "Objective-C class '" << *D << "' lacks a 'dealloc' instance method";
 
     BR.EmitBasicReport(D, Checker, name, categories::CoreFoundationObjectiveC,
                        os.str(), DLoc);
     return;
   }
 
-  // dealloc found.  Scan for missing [super dealloc].
-  if (MD->getBody() && !scan_dealloc(MD->getBody(), S)) {
-
-    const char* name = LOpts.getGC() == LangOptions::NonGC
-                       ? "missing [super dealloc]"
-                       : "missing [super dealloc] (Hybrid MM, non-GC)";
-
-    std::string buf;
-    llvm::raw_string_ostream os(buf);
-    os << "The 'dealloc' instance method in Objective-C class '" << *D
-       << "' does not send a 'dealloc' message to its super class"
-           " (missing [super dealloc])";
-
-    BR.EmitBasicReport(MD, Checker, name, categories::CoreFoundationObjectiveC,
-                       os.str(), DLoc);
-    return;
-  }
-
   // Get the "release" selector.
   IdentifierInfo* RII = &Ctx.Idents.get("release");
   Selector RS = Ctx.Selectors.getSelector(0, &RII);
 
   // Get the "self" identifier
   IdentifierInfo* SelfII = &Ctx.Idents.get("self");
 
   // Scan for missing and extra releases of ivars used by implementations