On Tue, Feb 14, 2012 at 11:09:44PM +0000, Sune Vuorela wrote: > On 2012-02-14, Kurt Roeckx <k...@roeckx.be> wrote: > > It was always my understanding that protected wasn't useful, > > because it's even more expensive. > > Can you come with a bit pointers or numbers about 'expensive' ?
So as far as I understand things the only way to make protected work without -fPIE is using text relocations. This has the following effects: - The text segment can no longer be read-only, and so can't be shared anymore. - You need a relocation for each use of the variable. And you really don't want text relocations. > > As far as I understand things, this is supposed to work, and might > > be a bug in the toolchain or dynamic linker. Which might also > > mean that they're trying to make use of a bug in the toolchain. > > It is not a bug in the toolchain. It is how the processor specific ABI > is. I'm assuming that you're talking about the small model of amd64. I can't see anything in the psABI that prevents this from working. But implementing it with text relocations is something you don't want, so I can understand that nobody implemented it. The bug in the toolchain is that it allows you to create broken binaries. Anyway, to avoid the copy relocations, I suggest you hide the symbol and make functions to be able to use it outside the DSO. Kurt -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20120215173938.ga16...@roeckx.be
