On 1/16/2013 1:35 PM, Corinna Vinschen wrote:
As far as I can tell it's an objcopy bug. The stripped version of the DLL has a normal relocation information which at one point ends in a NULL IMAGE_BASE_RELOCATION record, as expected. After calling `objcopy --add-gnu-debuglink', the relocation information is supposed to be the same as before, since the relocatable file content didn't change. Nevertheless, when stepping through the relocator code in rebase, it turns out that the former NULL IMAGE_BASE_RELOCATION record does not contain only 0 values anymore. Rather, it has been overwritten with some random(?) non-0 values, which rebase correctly interprets as the start of the next IMAGE_BASE_RELOCATION array. So rebase blunders along, thus either just SEGVing, if everything goes well, or, worst case, overwriting formerly correct information in the file with arbitrary data. This is a serious bug in objcopy in the current binutils. Given that cygport creates the debug info automatically, we might end up with spuriously broken DLLs in the distro. I checked with objcopy from the older binutils 2.51.53-2, and the problem did not show up. I also built the latest binutils release 2.23.1 and the problem also doesn't show, so we probably can get away with just a black eye by updating binutils to 2.23.1. Chris? Corinna
Chris, any news ? Marco -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
