On Thu, 27 Jun 2013, Yufeng Zhang wrote: > We need a reliable way to tell we are compiling for ILP32. On one hand LLP64 > support may be added in the future; on the other hand, not all AArch64
If thinking of adding a third ABI, that suggests you should be using something along the lines of _MIPS_SIM - a macro that's always defined, with an integer value depending on the ABI in used. > compilers may define _LP64 and __LP64__. Why should all such compilers define the ILP32 macros, but not all define the LP64 macros? Do you have an AArch64 equivalent of the ACLE that specifies such things? > Other ports like x86_64, ia64-hpux and pa-hpux also define one or both. If multiple ports define something, that might be an indication for defining it in target-independent code (like _LP64) rather than repeating it for more targets. Although of course the macros __SIZEOF_INT__, __SIZEOF_LONG__, __SIZEOF_LONG_LONG__ and __SIZEOF_POINTER__ have been around for a long time, so new macros would just be for convenience (which may nevertheless be a sensible reason to define macros) at the expense of startup time. -- Joseph S. Myers jos...@codesourcery.com
