Possible Duplicate:
Where and why do I have to put the “template” and “typename” keywords?
There appears to be a bug in GCC 4.5.3:
#include <type_traits>
template <bool isFundamentalType, bool isSomething>
struct Foo
{
template <typename T>
static inline void* Do(size_t size);
};
template <>
struct Foo<true, false>
{
template <typename T>
static inline void* Do(size_t size)
{
return NULL;
}
};
template <>
struct Foo<false, false>
{
template <typename T>
static inline void* Do(size_t size)
{
return NULL;
}
};
class Bar
{
};
template <typename T>
int Do(size_t size)
{
// The following fails
return (int) Foo<std::is_fundamental<T>::value, false>::Do<T>(size);
// This works -- why?
return (int) Foo<false, false>::Do<T>(size);
}
int main()
{
return Do<Bar>(10);
}
Compiled with
g++ bug.cpp -std=c++0x
Errors:
bug.cpp: In function ‘int Do(size_t)’:
bug.cpp:37:65: error: expected primary-expression before ‘>’ token
Is there a known workaround that would allow me to side step this issue?
EDIT: MSVC 2010 managed to compile this just fine.
You need to add template
:
return (int) Foo<std::is_fundamental<T>::value, false>::template Do<T>(size);
MSVC 2010 compiles the code because it doesn't handle templates correctly.
Side Note
MSVC also injects size_t
into the global namespace because of a long withstanding bug. Technically you need to include the proper header on other compilers.