RE: Big-endian Gcc on Intel IA32

[Etienne Lorrain <etienne_lorrain at yahoo dot fr>]

  Just a (maybe meaningless) comment on attributes:

 When you begin to describe your variables with __attribute__(()),
 for instance to optimise code size or speed, you also feel a need
 to test if the variable as such or such attributes, for instance in
 inline functions/macro. Let's take the example of align/alignof:

  struct longstruct mydata __attribute__((aligned(16)));

  static const struct longstruct emptydata = {};

  void init_mydata (struct longstruct *mydataptr)
  {
  if (alignof (emptydata) > 4)
      fast_memcpy(...);
    else
      slow_memcopy(...);
  }

  Maybe a more generic way to define and test attributes, at least
 for structure types, would be something like:

  typedef struct {
      unsigned field1, field2;
      char field3;
      const unsigned __aligned__ = 16; /* not counted in sizeof() */
      } an_aligned_16_type;

  an_aligned_16_type data;

  { if (data.__aligned__ == 16) {} else {} }

  In the same spirit:
  typedef struct {
      const unsigned __packed__ = 1;
      unsigned short d1;
      unsigned long d2;
      }

  typedef struct {
      const unsigned __segment__ = __segment_gs;
      unsigned char red;
      unsigned char green;
      unsigned char blue;
      } what_I_need_for_another_project;

  void fct (void)
  {
  const unsigned __aligned__ = 64;

  ....
  }

  The programmer could also define his own attributes.
  Would also not break too much "indent" and "lint" kind of software.

  No, I do not have the time to implement, sorry.
  Etienne.

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