Add an option to silence all analyzer warnings.

People have been incorrectly using "-analyzer-disable-checker" to
silence analyzer warnings on a file, when analyzing a project. Add
the "-analyzer-disable-all-checks" option, which would allow the
suppression and suggest it as part of the error message for
"-analyzer-disable-checker". The idea here is to compose this with
"--analyze" so that users can selectively opt out specific files from
static analysis.

llvm-svn: 216763

clang/include/clang/Basic/DiagnosticFrontendKinds.td

@@ -135,6 +135,9 @@ def warn_unknown_warning_specifier : Warning<
 
 def err_unknown_analyzer_checker : Error<
     "no analyzer checkers are associated with '%0'">;
+def note_suggest_disabling_all_checkers : Note<
+    "use -analyzer-disable-all-checks to disable all static analyzer checkers">;
+
 def warn_incompatible_analyzer_plugin_api : Warning<
     "checker plugin '%0' is not compatible with this version of the analyzer">,
     InGroup<DiagGroup<"analyzer-incompatible-plugin"> >;

clang/include/clang/Driver/CC1Options.td

@@ -108,6 +108,9 @@ def analyzer_disable_checker : Separate<["-"], "analyzer-disable-checker">,
 def analyzer_disable_checker_EQ : Joined<["-"], "analyzer-disable-checker=">,
   Alias<analyzer_disable_checker>;
 
+def analyzer_disable_all_checks : Flag<["-"], "analyzer-disable-all-checks">,
+  HelpText<"Disable all static analyzer checks">;
+
 def analyzer_checker_help : Flag<["-"], "analyzer-checker-help">,
   HelpText<"Display the list of analyzer checkers that are available">;
 

clang/include/clang/StaticAnalyzer/Core/AnalyzerOptions.h

@@ -137,6 +137,13 @@ public:
   unsigned maxBlockVisitOnPath;
   
   
+  /// \brief Disable all analyzer checks.
+  ///
+  /// This flag allows one to disable analyzer checks on the code processed by
+  /// the given analysis consumer. Note, the code will get parsed and the
+  /// command-line options will get checked.
+  unsigned DisableAllChecks : 1;
+
   unsigned ShowCheckerHelp : 1;
   unsigned AnalyzeAll : 1;
   unsigned AnalyzerDisplayProgress : 1;
@@ -420,6 +427,7 @@ public:
     AnalysisConstraintsOpt(RangeConstraintsModel),
     AnalysisDiagOpt(PD_HTML),
     AnalysisPurgeOpt(PurgeStmt),
+    DisableAllChecks(0),
     ShowCheckerHelp(0),
     AnalyzeAll(0),
     AnalyzerDisplayProgress(0),

clang/lib/Frontend/CompilerInvocation.cpp

@@ -215,6 +215,8 @@ static bool ParseAnalyzerArgs(AnalyzerOptions &Opts, ArgList &Args,
   }
 
   Opts.ShowCheckerHelp = Args.hasArg(OPT_analyzer_checker_help);
+  Opts.DisableAllChecks = Args.hasArg(OPT_analyzer_disable_all_checks);
+
   Opts.visualizeExplodedGraphWithGraphViz =
     Args.hasArg(OPT_analyzer_viz_egraph_graphviz);
   Opts.visualizeExplodedGraphWithUbiGraph =

clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp

@@ -314,7 +314,7 @@ public:
   /// analyzed. This allows to redefine the default inlining policies when
   /// analyzing a given function.
   ExprEngine::InliningModes
-  getInliningModeForFunction(const Decl *D, const SetOfConstDecls &Visited);
+    getInliningModeForFunction(const Decl *D, const SetOfConstDecls &Visited);
 
   /// \brief Build the call graph for all the top level decls of this TU and
   /// use it to define the order in which the functions should be visited.
@@ -513,6 +513,11 @@ void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
   if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred())
     return;
 
+  // Don't analyze if the user explicitly asked for no checks to be performed
+  // on this file.
+  if (Opts->DisableAllChecks)
+    return;
+
   {
     if (TUTotalTimer) TUTotalTimer->startTimer();
 

clang/lib/StaticAnalyzer/Frontend/CheckerRegistration.cpp

@@ -118,9 +118,12 @@ CheckerManager *ento::createCheckerManager(AnalyzerOptions &opts,
   checkerMgr->finishedCheckerRegistration();
 
   for (unsigned i = 0, e = checkerOpts.size(); i != e; ++i) {
-    if (checkerOpts[i].isUnclaimed())
+    if (checkerOpts[i].isUnclaimed()) {
       diags.Report(diag::err_unknown_analyzer_checker)
           << checkerOpts[i].getName();
+      diags.Report(diag::note_suggest_disabling_all_checkers);
+    }
+
   }
 
   return checkerMgr.release();

clang/test/Analysis/disable-all-checks.c

@@ -0,0 +1,10 @@
+// RUN: %clang_cc1 -analyze -analyzer-checker=core -analyzer-store=region -analyzer-disable-all-checks -verify %s
+// RUN: %clang_cc1 -analyze -analyzer-disable-all-checks -analyzer-checker=core -analyzer-store=region -verify %s
+// RUN: not %clang_cc1 -analyze -analyzer-checker=core -analyzer-store=region -analyzer-disable-checker -verify %s 2>&1 | FileCheck %s
+// expected-no-diagnostics
+
+// CHECK: use -analyzer-disable-all-checks to disable all static analyzer checkers
+int buggy() {
+  int x = 0;
+  return 5/x; // no warning
+}