Initial support for dumping DWARF corresponding to Swift code

src/common/language.h

 // -*- mode: c++ -*-
 
 // Copyright (c) 2010 Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
@@ skipping 59 matching lines @@
   // parent's name, and that we don't need to know anything else about
   // the parent or the child (say, their DIEs' tags) to do the job.
   // This is true for the languages we support at the moment, and
   // keeps things concrete. Perhaps a more refined operation would
   // take into account the parent and child DIE types, allow languages
   // to use their own data type for complex parent names, etc. But if
   // C++ doesn't need all that, who would?
   virtual string MakeQualifiedName (const string &parent_name,
                                     const string &name) const = 0;
 
+  // Special return value from DemangleName() to indicate that demangling was
+  // not performed because it’s not appropriate to attempt.
+  static const int kDontDemangle;
+
+  // Wraps abi::__cxa_demangle() or similar for languages where appropriate.
+  // Returns the demangler's status value, or kDontDemangle if demangling (and
+  // error reporting) is inappropriate. Returns 0 on success, with |demangled|
+  // set.
+  virtual int DemangleName(const string& mangled, std::string* demangled)

[Ted Mielczarek, 2016/09/14 10:20:10]

I think it would be better to make this return an enum with three possible
values:
* Success
* Failure
* DontDemangle

The `__cxa_demangle` status codes aren't likely to be of any use to the caller
anyway.

+      const {
+    demangled->clear();
+    return kDontDemangle;
+  }
+
   // Instances for specific languages.
   static const Language * const CPlusPlus,
                         * const Java,
+                        * const Swift,
                         * const Assembler;
 };
 
 } // namespace google_breakpad
 
 #endif  // COMMON_LINUX_LANGUAGE_H__