search for: exxecutable

...finition, which was left, is in a piece of debug info related to deleted > code. According to zero-length rule, that definition could be ignored, and > finally, incomplete debug info could be used. > Yeah, I think the bug there is the linker dropping object files just because they have no exxecutable code in them - I think the patch that did that was reverted, if I'm remembering correctly. > > So, it probably should be forbidden to generate debug_info, which could > become incomplete after removing pieces related to zero length address > ranges. Otherwise, creating zero-length...

...ith the >same approach as debug_ranges, but I haven't looked at debug_aranges in a >long time. > >I guess the only remaining question is: Since it's possible to have code on >some systems down at address zero, or close enough to it that [0, length) >might overlap with real exxecutable code addresses - does anyone know of >the inverse: where code is mapped up near uint32 max? Such that that usage >wouldn't be able to sacrifice uint32 max - 1 to use as a blessed value here? > >- Dave > > >> >> >> --paulr >> >> >> >> *...

As has been mentioned elsewhere, Sony generally fixes up references from debug info to stripped functions (of any length) using -1, because that's a less-likely-to-be-real address than 0x0 or 0x1. (0x0 is a typical base address for shared libraries, I'd think using it has the potential to mislead various consumers.) For .debug_ranges we use -2, because both a 0/0 pair and a -1/-1 pair

...looked at debug_aranges in a > > >long time. > > > > > >I guess the only remaining question is: Since it's possible to have code > > on > > >some systems down at address zero, or close enough to it that [0, length) > > >might overlap with real exxecutable code addresses - does anyone know of > > >the inverse: where code is mapped up near uint32 max? Such that that > > usage > > >wouldn't be able to sacrifice uint32 max - 1 to use as a blessed value > > here? > > > > > >- Dave > > > > &g...

...> > > > > > >I guess the only remaining question is: Since it's possible to have > > code > > > > on > > > > >some systems down at address zero, or close enough to it that [0, > > length) > > > > >might overlap with real exxecutable code addresses - does anyone know > > of > > > > >the inverse: where code is mapped up near uint32 max? Such that that > > > > usage > > > > >wouldn't be able to sacrifice uint32 max - 1 to use as a blessed > > value > > > > here...

...only remaining question is: Since it's possible to have > >> > code > >> > > > on > >> > > > >some systems down at address zero, or close enough to it that [0, > >> > length) > >> > > > >might overlap with real exxecutable code addresses - does anyone know > >> > of > >> > > > >the inverse: where code is mapped up near uint32 max? Such that that > >> > > > usage > >> > > > >wouldn't be able to sacrifice uint32 max - 1 to use as a blessed >...

So there have been several recent discussions about the issues around DWARF-agnostic linking and gc-sections, linkonce function definitions being dropped, etc - and just how much DWARF-awareness would be suitable in a linker to help with this situation. I'd like to discuss a narrower instance of this issue: Zero length gc'd/deduplicated functions. LLVM seems to at least produce zero

...ossible to have > >> >> > code > >> >> > > > on > >> >> > > > >some systems down at address zero, or close enough to it that [0, > >> >> > length) > >> >> > > > >might overlap with real exxecutable code addresses - does anyone know > >> >> > of > >> >> > > > >the inverse: where code is mapped up near uint32 max? Such that that > >> >> > > > usage > >> >> > > > >wouldn't be able to sacrifice uin...