get this to compile with g++-mp-4.8

c++/src/capnp/compiler/compiler.c++

@@ -211,7 +211,7 @@ private:
 class Compiler::Impl: public SchemaLoader::LazyLoadCallback {
 public:
   Impl();
-  virtual ~Impl();
+  virtual ~Impl() noexcept(false);
 
   uint64_t add(const Module& module, Mode mode) const;
   kj::Maybe<uint64_t> lookup(uint64_t parent, kj::StringPtr childName) const;

c++/src/capnp/compiler/compiler.h

@@ -56,7 +56,7 @@ class Compiler {
 
 public:
   Compiler();
-  ~Compiler();
+  ~Compiler() noexcept(false);
   KJ_DISALLOW_COPY(Compiler);
 
   enum Mode {

c++/src/capnp/compiler/lexer.h

@@ -53,7 +53,7 @@ public:
   // `orphanage` is used to allocate Cap'n Proto message objects in the result.  `inputStart` is
   // a pointer to the beginning of the input, used to compute byte offsets.
 
-  ~Lexer();
+  ~Lexer() noexcept(false);
 
   class ParserInput: public kj::parse::IteratorInput<char, const char*> {
     // Like IteratorInput<char, const char*> except that positions are measured as byte offsets

c++/src/capnp/compiler/module-loader.h

@@ -40,7 +40,7 @@ public:
 
   KJ_DISALLOW_COPY(ModuleLoader);
 
-  ~ModuleLoader();
+  ~ModuleLoader() noexcept(false);
 
   void addImportPath(kj::String path);
   // Add a directory to the list of paths that is searched for imports that start with a '/'.

c++/src/capnp/compiler/parser.h

@@ -52,7 +52,7 @@ public:
   // `orphanage` is used to allocate Cap'n Proto message objects in the result.  `inputStart` is
   // a pointer to the beginning of the input, used to compute byte offsets.
 
-  ~CapnpParser();
+  ~CapnpParser() noexcept(false);
 
   KJ_DISALLOW_COPY(CapnpParser);