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/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 =