On 07/22/16 14:28, Richard Biener wrote: > On Thu, 21 Jul 2016, Bernd Edlinger wrote: > >> Hi, >> >> based on the discussion here, I have updated my patch again... >> >> This is the rest of the patch, which removes outdated function names, >> and creates built-in definitions for vfork, getcontext, savectx. >> These built-ins have the return_twice attribute but not the >> leaf attribute, because we do not really know, what these functions >> do. >> >> The reason for ceating the builtin functions is, that I would like >> to get a warning about conflicting builtin definition if someone >> accidentally picks the name of one of these less well known special >> functions, which are _not_ reserved names in most environments. >> >> I do not define builtins (without __builtin_ prefix) for setjmp and >> sigsetjmp because these are like wildcards, and they fall in the >> well-known category anyways. >> >> I still retain the handling of these functions in special_function_p >> because even in a free standing environment, returning >> ECF_RETURNS_TWICE is on the safe side. >> >> >> >> Is it OK for trunk after boot-strap and regression-testing? > > As DEF_EXT_LIB_BUILTIN won't have any effect with -std=c99 for example > I don't think having the builtins helps much. I think we have > this name-matching function for correctness purposes (and even my > local glibc doesn't declare [v]fork as returning twice nor does > the existing BUILT_IN_FORK btw). >
fork does not have to, but it is a no-leaf function because it calls pthread_atfork handlers. So it has to be __TROWNL. I think in the long run the header files just should be fixed. But that will take a while... Bernd.
