Hi Marek, On Fri, 5 Mar 2021 at 10:24, Marek Behun <marek.be...@nic.cz> wrote: > > On Fri, 5 Mar 2021 09:58:34 -0700 > Simon Glass <s...@chromium.org> wrote: > > > Hi Marek, > > > > On Fri, 5 Mar 2021 at 09:50, Marek Behun <marek.be...@nic.cz> wrote: > > > > > > On Fri, 5 Mar 2021 09:39:53 -0700 > > > Simon Glass <s...@chromium.org> wrote: > > > > > > > Hi Marek, > > > > > > > > On Fri, 5 Mar 2021 at 08:37, Marek Behun <marek.be...@nic.cz> wrote: > > > > > > > > > > On Fri, 5 Mar 2021 11:00:45 +0800 > > > > > Bin Meng <bmeng...@gmail.com> wrote: > > > > > > > > > > > On Wed, Mar 3, 2021 at 12:13 PM Marek Behún <marek.be...@nic.cz> > > > > > > wrote: > > > > > > > > > > > > > > When building with LTO, the system libc's `errno` variable used in > > > > > > > arch/sandbox/cpu/os.c conflicts with U-Boot's `errno` (defined in > > > > > > > lib/errno.c) with the following error: > > > > > > > .../ld: errno@@GLIBC_PRIVATE: TLS definition in /lib64/libc.so.6 > > > > > > > section .tbss mismatches non-TLS reference in > > > > > > > /tmp/u-boot.EQlEXz.ltrans0.ltrans.o > > > > > > > > > > > > Do you know if this is the expected behavior when enabling LTO on > > > > > > the compiler? > > > > > > > > > > I don't, but this is a bug anyway. The symbol clashes with the symbol > > > > > from glibc. Does somebody know whether the usage of this symbol in > > > > > os.c > > > > > does really use glibc's version or U-Boot's one? > > > > > > > > It is intended to use glibc's version. In fact I don't think U-Boot > > > > should have an errno. We return errors in each case, as does Linux. > > > > > > The problem is that libc defines errno as a thread-local variable or, > > > in older version, as a macro expading to a function dereference, i.e. > > > #define errno (*__get_threads_errno()) > > > But U-Boot usis the errno symbol defined in include/errno.h as a symbol. > > > > > > So in order for these two symbols not to clash (in case libc is using > > > thread-local symbol with name errno), we need to rename the U-Boot > > > errno variable's symbol name. > > > > Rename is OK, but can we delete it instead? I really don't think it > > should be there. > > We can't simply delete it. The whole u-boot is using the errno symbol > from include/errno.h and if we want the whole u-boot to use libc's > symbol we need to code include/errno.h to declare it in the same way as > libc, which may be different for different libcs.
OK... Heinrich I don't think the fs needs to use errno, or perhaps it should have its own local version. It's just not nice to have a global error number IMO. Anyway, this is for future discussion, not for Marek to worry about. I am fine with Marek's solution. Regards, Simon