Hi,

the following bit of code:

template <int N, typename T> struct Foo
{
  typedef T __attribute__((vector_size(N*sizeof(T)))) type;
};

compiles fine with gcc 4.7.2, however when compiled with clang 3.2 I get:

foo.cc:4:41: error: expected ')'
  typedef T __attribute__((vector_size(N*sizeof(T)))) type;
                                        ^
                                        )
foo.cc:4:41: error: expected ')'
  typedef T __attribute__((vector_size(N*sizeof(T)))) type;
                                        ^
                                        )
foo.cc:4:53: error: expected member name or ';' after declaration specifiers
  typedef T __attribute__((vector_size(N*sizeof(T)))) type;
  ~~~~~~~~~                                         ^

Moreover even doing:

template <int N, typename T> struct Foo
{
  typedef T __attribute__((vector_size(16))) type;
};

does not work and gives:

foo.cc:4:28: error: invalid vector element type 'T'
  typedef T __attribute__((vector_size(16))) type;
                           ^

The only way to get it to work is to eliminate the dependency on the T template argument:

template <int N, typename T> struct Foo
{
  typedef int __attribute__((vector_size(16))) type;
};

compiles fine on both clang 3.2 and gcc 4.7.2

Any idea?

Ciao,
Giulio