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> >>> =20 > >>> ElfW(Addr) r_ldbase; /* Base address the linker is loaded at. *= / > >>> + > >>> + /* Link to next r_debug struct. Each r_debug struct represents a > >>> + different namespace. The first r_debug struct is the default= . */ > >>> + struct r_debug *next; > >>> }; > >>> =20 > >>> /* This is the instance of that structure used by the dynamic linker= . */ > >>=20 > >> How has this patch been tested? I expect that it will cause an abilis= t > >> mismatch for the _r_debug symbol in the dynamic linker. > >>=20 > >> If we go this route to add this capability, I think we have to add a n= ew > >> symbol version for the _r_debug symbol, and keep the old one at the > >> previous size. > >>=20 > >> How is your compatibility experience with the size and version change? > >> How many tools need updating before they work again? > >>=20 > >> A different approach would add another symbol (parallel to _r_debug) t= o > >> store this data. This would avoid the need for any immediate tool > >> updates. > > > > I mention this in my response to the cover letter in this series. >=20 > Your explanation there was truncated. >=20 > > This patch is probably unacceptable as-is because of application > > expectations. >=20 > But perhaps Cisco's experience shows that our worries are unfounded? I don't know that we can confirm this. Per my understanding these changes h= ave been maintained as one off changes which haven't entered our product yet. W= e're now currently trying to add this to our product. We use OpenEmbedded to bui= ld an SDK which is then used in our product. The tooling in typical rebuilt against any new glibc which we have, and we don't reuse binaries from the p= rior builds which may have a different glibc (even different patch level). Daniel=