Compiler error coming out of yaml-cpp

Question

I'm attempting to integrate yaml-cpp into a project, but I'm seeing some unexpected errors out of GCC. For example:

g++ -c -ggdb3 -ansi -Wall -Werror -pedantic-errors src/commands-tz.cpp -o obj/commands-tz.o
In file included from /usr/local/include/yaml-cpp/conversion.h:9,
                 from /usr/local/include/yaml-cpp/node.h:8,
                 from /usr/local/include/yaml-cpp/parser.h:8,
                 from /usr/local/include/yaml-cpp/yaml.h:8,
                 from src/note.h:26,
                 from src/commands-tz.cpp:297:
/usr/local/include/yaml-cpp/traits.h:26: error: expected identifier before ‘(’ token
/usr/local/include/yaml-cpp/traits.h:26: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:26: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:26: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/traits.h:31: error: expected identifier before ‘(’ token
/usr/local/include/yaml-cpp/traits.h:31: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:31: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:31: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/traits.h:34: error: expected identifier before ‘(’ token
/usr/local/include/yaml-cpp/traits.h:34: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:34: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:34: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/traits.h:37: error: expected identifier before ‘(’ token
/usr/local/include/yaml-cpp/traits.h:37: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:37: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:37: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/traits.h:42: error: expected identifier before ‘(’ token
/usr/local/include/yaml-cpp/traits.h:42: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:42: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:42: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/traits.h:45: error: expected identifier before ‘(’ token
/usr/local/include/yaml-cpp/traits.h:45: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:45: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/traits.h:45: error: expected unqualified-id before ‘)’ token

Another example:

In file included from /usr/local/include/yaml-cpp/nodeimpl.h:8,
                 from /usr/local/include/yaml-cpp/node.h:139,
                 from /usr/local/include/yaml-cpp/parser.h:8,
                 from /usr/local/include/yaml-cpp/yaml.h:8,
                 from src/note.h:26,
                 from src/commands-tz.cpp:297:
/usr/local/include/yaml-cpp/nodeutil.h:9: error: expected nested-name-specifier before ‘(’ token
/usr/local/include/yaml-cpp/nodeutil.h:9: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/nodeutil.h:9: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/nodeutil.h:9: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/nodeutil.h:14: error: expected nested-name-specifier before ‘(’ token
/usr/local/include/yaml-cpp/nodeutil.h:14: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/nodeutil.h:14: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/nodeutil.h:14: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/nodeutil.h:19: error: expected nested-name-specifier before ‘(’ token
/usr/local/include/yaml-cpp/nodeutil.h:19: error: expected ‘)’ before numeric constant
/usr/local/include/yaml-cpp/nodeutil.h:19: error: expected ‘>’ before numeric constant
/usr/local/include/yaml-cpp/nodeutil.h:19: error: expected unqualified-id before ‘)’ token
/usr/local/include/yaml-cpp/nodeutil.h:24: error: ‘is_index_type_with_check’ is not a template
/usr/local/include/yaml-cpp/nodeutil.h:24: error: explicit specialization of non-template ‘YAML::is_index_type_with_check’

My platform is Fedora (2.6.32 kernel), GCC 4.4.1, and yaml-cpp 0.2.5. There are many, many other errors. To the naked eye, this seems like a problem within yaml-cpp, but experience tells me I'm probably the one at fault. Any ideas?

UPDATE

The file traits.h contains the following:

namespace YAML
{
        template <typename>
        struct is_numeric { enum { value = false }; };

        template <> struct is_numeric <char> { enum { value = true }; };
        template <> struct is_numeric <unsigned char> { enum { value = true }; };
        template <> struct is_numeric <int> { enum { value = true }; };
        template <> struct is_numeric <unsigned int> { enum { value = true }; };
        template <> struct is_numeric <long int> { enum { value = true }; };
        template <> struct is_numeric <unsigned long int> { enum { value = true }; };
        template <> struct is_numeric <short int> { enum { value = true }; };
        template <> struct is_numeric <unsigned short int> { enum { value = true }; };
        template <> struct is_numeric <long long> { enum { value = true }; };
        template <> struct is_numeric <unsigned long long> { enum { value = true }; };
        template <> struct is_numeric <float> { enum { value = true }; };
        template <> struct is_numeric <double> { enum { value = true }; };
        template <> struct is_numeric <long double> { enum { value = true }; };

        template <bool, class T = void>
        struct enable_if_c {
          typedef T type;
        };

        template <class T>
        struct enable_if_c<false, T> {};

        template <class Cond, class T = void>
        struct enable_if : public enable_if_c<Cond::value, T> {};

        template <bool, class T = void>
        struct disable_if_c {
          typedef T type;
        };

        template <class T>
        struct disable_if_c<true, T> {};

        template <class Cond, class T = void>
        struct disable_if : public disable_if_c<Cond::value, T> {};
}

And nodeutil.h contains:

namespace YAML
{
        template <typename T, typename U>
        struct is_same_type {
                enum { value = false };
        };

        template <typename T>
        struct is_same_type<T, T> {
                enum { value = true };
        };

        template <typename T, bool check>
        struct is_index_type_with_check {
                enum { value = false };
        };

        template <> struct is_index_type_with_check<std::size_t, false> { enum { value = true }; };

#define MAKE_INDEX_TYPE(Type) \
        template <> struct is_index_type_with_check<Type, is_same_type<Type, std::size_t>::value> { enum { value = true }; }

        MAKE_INDEX_TYPE(int);
        MAKE_INDEX_TYPE(unsigned);
        MAKE_INDEX_TYPE(short);
        MAKE_INDEX_TYPE(unsigned short);
        MAKE_INDEX_TYPE(long);
        MAKE_INDEX_TYPE(unsigned long);

#undef MAKE_INDEX_TYPE

        template <typename T>
        struct is_index_type: public is_index_type_with_check<T, false> {};

        // messing around with template stuff to get the right overload for operator [] for a sequence
        template <typename T, bool b>
        struct _FindFromNodeAtIndex {
                const Node *pRet;
                _FindFromNodeAtIndex(const Node&, const T&): pRet(0) {}
        };

        template <typename T>
        struct _FindFromNodeAtIndex<T, true> {
                const Node *pRet;
                _FindFromNodeAtIndex(const Node& node, const T& key): pRet(node.FindAtIndex(static_cast<std::size_t>(key))) {}
        };

        template <typename T>
        inline const Node *FindFromNodeAtIndex(const Node& node, const T& key) {
                return _FindFromNodeAtIndex<T, is_index_type<T>::value>(node, key).pRet;
        }
}

Answer 1

I would suggest you try removing "using namespace X;" - particularly where X == YAML. Your error messages may get more insightful that way - as it looks like you're having name clashes. Another trick is to see what the preprocessor is spitting out - with G++ you can run your compile line with -E (instead of -c) and pipe the output to a file. Then you can see what the compiler is getting (rather then the original source, or what the preprocessor is getting).

Answer 2

You seem to be inside include hell. The traits.h file you posted contains no '(', but gcc complains about what comes before a '('. That might mean that you are including something that has a macro with the same name as something in this file. Try reordering the includes in your project and see if it make any difference.