On Thu, 16 May 2013, DJ Delorie wrote: > SIZE_TYPE is compared - with individual strcmp's! - against a fixed > set of C types, instead of using some sort of table lookup to support > non-power-of-two types.
Joern had a patch (as of December 2010, possibly updated since then) to convert at least some such macros to use enum values (stdint.h ones, anyway) to use enum values rather than strings as a cleaner API. Though that wouldn't be sufficient for what you want. The front-end type pieces of Bernd's changes didn't go in, since they embedded things specific to 40-bit types all over the place rather than providing a more general infrastructure for types of architecture-specific precision. Logically I'd like a way for an architecture to define a set of precisions for which there are __intN keywords and associated __intN, unsigned __intN types (plus the _Complex versions of those). Then maybe the values given for types such as SIZE_TYPE would be either an enum value for a standard type, or e.g. ITK_INTN (40) or ITK_UNSIGNED_INTN (40), where ITK_INTN expands to some expression giving a value of the enum type not corresponding to any of the standard named types. Likewise for floating-point types. DTS 18661-3 (the third part of the draft ISO C bindings to IEEE 754-2008) defines types _FloatN, where N is 16, 32, 64, or >= 128 and a multiple of 32 _DecimalN, where N >= 32 and a multiple of 32 and _Complex variants of the _FloatN types, where the particular set supported depends on the implementation (and so for GCC would depend on the architecture). Again, these should be keywords. (I don't think any of the above should be particularly hard to implement.) -- Joseph S. Myers jos...@codesourcery.com
