fix comment and default value

[YolandaCY]

Abandon this as submitted by mistake. Sorry for any inconvenience.

lld/COFF/Options.td

def lto_obj_path : P<
     "lto-obj-path",
     "output native object for merged LTO unit to this path">;
 def lto_cs_profile_generate: F<"lto-cs-profile-generate">,
     HelpText<"Perform context sensitive PGO instrumentation">;
 def lto_cs_profile_file : P<"lto-cs-profile-file",
     "Context sensitive profile file path">;
 defm lto_cspgo_warn_mismatch: B<
      "lto-cspgo-warn-mismatch",
-     "turn on warnings about profile mismatch (default)>",
-     "turn off warnings about profile mismatch">;
+     "turn on warnings about profile cfg mismatch (default)>",
+     "turn off warnings about profile cfg mismatch">;
 def dash_dash_version : Flag<["--"], "version">,
   HelpText<"Display the version number and exit">;
 def threads
     : P<"threads", "Number of threads. '1' disables multi-threading. By "
                    "default all available hardware threads are used">;
 def call_graph_ordering_file: P<
     "call-graph-ordering-file", 
     "Layout sections to optimize the given callgraph">;

llvm/include/llvm/LTO/Config.h

struct Config {
   bool Freestanding = false;
 
   /// Disable entirely the optimizer, including importing for ThinLTO
   bool CodeGenOnly = false;
 
   /// Run PGO context sensitive IR instrumentation.
   bool RunCSIRInstr = false;
 
-  /// Turn on/off warnings about PGO context sensitive profile mismatch.
-  bool CSPGOWarnMismatch = false;
+  /// Turn on/off the warning about a hash mismatch in the context sensitive
+  /// PGO profile data.
+  bool CSPGOWarnMismatch = true;
 
   /// Asserts whether we can assume whole program visibility during the LTO
   /// link.
   bool HasWholeProgramVisibility = false;
 
   /// Always emit a Regular LTO object even when it is empty because no Regular
   /// LTO modules were linked. This option is useful for some build system which
   /// want to know a priori all possible output files.