On Fri, 8 May 2015, Rich Felker wrote: > On Fri, May 08, 2015 at 03:41:31PM +0100, Szabolcs Nagy wrote: > > > I.e. as it stands this patch is not OK for backporting to GCC 5 > > > without further discussion. > > > > > > There is also the perspective that we should be able to aim for > > > an ABI variant agnostic dynamic linker at some point over the next > > > year by working towards a build that truly uses no float and is > > > hence compatible with all the ABI variants. > > > > i'm not sure what you mean by 'a build that truly uses no float' > > > > i thought the direction is to have a potentially hard float abi > > with kernel emulation when the fpu is not present. > > I think Matthew's idea was that the dynamic linker could be agnostic > since it doesn't need floating point arithmetic itself, then load
Note that however the dynamic linker does properly need to save and restore call-clobbered registers used for argument passing (because of IFUNCs, user-provided malloc, audit hooks etc. that might affect them even if the dynamic linker itself doesn't); see <https://sourceware.org/ml/libc-alpha/2014-01/msg00673.html>. So any floating-point-agnostic dynamic linker would, if fixing the bugs around not saving / restoring such registers, need to have runtime-conditional code to save and restore them rather than simple compile-time conditionals. -- Joseph S. Myers jos...@codesourcery.com
