On Sat, 2020-02-22 at 18:07 -0600, Segher Boessenkool wrote: > > > > so I don't believe they are ever used by default -- in this case > > V_FUNCTION_BEGIN doesn't add to the .opd section with .name, .TOC base, > > etc. > > > > Manually setting VDS64_HAS_DESCRIPTORS results in a vdso64.so in which > > binutils tools like readelf properly report functions with symbol type > > FUNC instead of NOTYPE. > > > > Are there pieces of the build/etc toolchain unprepared for function > > descriptors? I'm just trying to figure out why the code defaults to > > unsetting them. > > Because direct calls are faster than indirect calls? Ben might have a > fuller explanation, cc:ing him.
I don't remember why :-) I think I didn't want to mess with the OPD fixup in glibc back then. Ben.
