On Tue, Nov 11, 2014 at 8:02 AM, H.J. Lu <hjl.to...@gmail.com> wrote: > On Mon, Nov 10, 2014 at 11:42 AM, H.J. Lu <hjl.to...@gmail.com> wrote: >> On Mon, Nov 10, 2014 at 5:44 AM, Richard Biener >> <richard.guent...@gmail.com> wrote: >>> On Mon, Nov 10, 2014 at 2:43 PM, Jakub Jelinek <ja...@redhat.com> wrote: >>>> On Mon, Nov 10, 2014 at 05:32:32AM -0800, H.J. Lu wrote: >>>>> On Mon, Nov 10, 2014 at 4:05 AM, Jakub Jelinek <ja...@redhat.com> wrote: >>>>> > On Mon, Nov 10, 2014 at 12:50:44PM +0100, Richard Biener wrote: >>>>> >> On Sun, Nov 9, 2014 at 5:46 PM, H.J. Lu <hongjiu...@intel.com> wrote: >>>>> >> > Hi, >>>>> >> > >>>>> >> > r216964 disables bootstrap for libcc1 which exposed 2 things: >>>>> >> > >>>>> >> > 1. libcc1 isn't compiled with LTO even when GCC is configured with >>>>> >> > "--with-build-config=bootstrap-lto". It may be intentional since >>>>> >> > libcc1 is disabled for bootstrap. >>>>> >> > 2. -fPIC isn't used to created libcc1.so, which is OK if libcc1 is >>>>> >> > compiled with LTO which remembers PIC option. >>>>> >> >>>>> >> Why is this any special to LTO? If it is then it looks like a LTO >>>>> >> (driver) issue to me? Why are we linking the pic libibterty into >>>>> >> a non-pic libcc1? >>>>> > >>>>> > I admit I haven't tried LTO bootstrap, but from normal bootstrap logs, >>>>> > libcc1 is built normally using libtool using -fPIC only, and linked into >>>>> > libcc1.so.0.0.0 and libcc1plugin.so.0.0.0, and of course against the >>>>> > pic/libiberty.a, because we need PIC code in the shared libraries. >>>>> > So, I don't understand the change at all. >>>>> > >>>>> > Jakub >>>>> >>>>> This is the command line to build libcc1.la: >>>> >>>> Sure, but there was -fPIC used to compile all the *.o files that are being >>>> linked into libcc1.so, so LTO should know that. >>> >>> And it does. If not please file a bug with a smaller testcase than libcc1 >>> and libiberty. >>> >> >> There is nothing wrong with linker. It is a slm-lto bug in libtool. I >> uploaded >> a testcase at >> >> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33931 >> > > My patch is a backport of libtool LTO support: > > commit b81fd4ef009c24a86a7e64727ea09efb410ea149 > Author: Ralf Wildenhues <ralf.wildenh...@gmx.de> > Date: Sun Aug 29 17:31:29 2010 +0200 > > Support GCC LTO on GNU/Linux. > > * libltdl/config/ltmain.m4sh (func_mode_link): Allow through > flags matching -O*, -flto*, -fwhopr, -fuse-linker-plugin. > * libltdl/m4/libtool.m4 (_LT_CMD_GLOBAL_SYMBOLS): Drop symbols > starting with __gnu_lto. > (_LT_LINKER_SHLIBS) [linux] <archive_cmds, archive_expsyms_cmds>: > Add $pic_flag for GCC. > (_LT_LANG_CXX_CONFIG) [linux] <archive_cmds, archive_expsyms_cmds>: > Likewise. > (_LT_SYS_HIDDEN_LIBDEPS): Ignore files matching *.lto.o. > * NEWS: Update. > > Signed-off-by: Ralf Wildenhues <ralf.wildenh...@gmx.de> > > OK to install? >
Ping. Stage 1 will be closed tomorrow. I'd like to restore LTO bootstrap. -- H.J.