Add an experimental flag -fsanitize-memory-use-after-dtor.

This flag will enable detection of use-after-destructor (but before
memory deallocation) bugs. No actual functionality yet.

https://code.google.com/p/address-sanitizer/issues/detail?id=73

Patch by Naomi Musgrave.

llvm-svn: 241935

clang/lib/Frontend/CompilerInvocation.cpp

@@ -557,6 +557,8 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
       Args.hasArg(OPT_fsanitize_coverage_8bit_counters);
   Opts.SanitizeMemoryTrackOrigins =
       getLastArgIntValue(Args, OPT_fsanitize_memory_track_origins_EQ, 0, Diags);
+  Opts.SanitizeMemoryUseAfterDtor =
+      Args.hasArg(OPT_fsanitize_memory_use_after_dtor);
   Opts.SSPBufferSize =
       getLastArgIntValue(Args, OPT_stack_protector_buffer_size, 8, Diags);
   Opts.StackRealignment = Args.hasArg(OPT_mstackrealign);