ELF: Add more variants of ignored flags.

[ruiu]

LGTM

ELF/Options.td

196

I'd name _eq instead of _EQ.

ELF/Options.td

 
 // Ignore LTO plugin-related options.
 // clang -flto passes -plugin and -plugin-opt to the linker. This is required
 // for ld.gold and ld.bfd to get LTO working. But it's not for lld which doesn't
 // rely on a plugin. Instead of detecting which linker is used on clang side we
 // just ignore the option on lld side as it's easier. In fact, the linker could
 // be called 'ld' and understanding which linker is used would require parsing of
 // --version output.
-def plugin : Separate<["-"], "plugin">;
-def plugin_opt : Joined<["-"], "plugin-opt=">;
+def plugin : Separate<["--", "-"], "plugin">;
+def plugin_EQ : Joined<["--", "-"], "plugin=">;
+def plugin_opt : Separate<["--", "-"], "plugin-opt">;
+def plugin_opt_EQ : Joined<["--", "-"], "plugin-opt=">;
 
 // Options listed below are silently ignored for now for compatibility.
 def fatal_warnings : Flag<["--"], "fatal-warnings">;
 def no_add_needed : Flag<["--"], "no-add-needed">;
 def no_fatal_warnings : Flag<["--"], "no-fatal-warnings">;
 def no_warn_common : Flag<["--", "-"], "no-warn-common">;
 def no_warn_mismatch : Flag<["--"], "no-warn-mismatch">;
 def rpath_link : Separate<["--", "-"], "rpath-link">;
+def rpath_link_EQ : Joined<["--", "-"], "rpath-link=">;
 def version_script : Separate<["--"], "version-script">;
 def warn_shared_textrel : Flag<["--"], "warn-shared-textrel">;
 def G : Separate<["-"], "G">;
 
 // Aliases for ignored options
 def alias_version_script_version_script : Joined<["--"], "version-script=">, Alias<version_script>;
 
 // Debugging options
 def save_temps : Flag<["-"], "save-temps">;