On Fri, Nov 14, 2014 at 12:15 AM, H.J. Lu <hjl.to...@gmail.com> wrote: > 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.
Bugfixing is still possible after that date. I suppose you don't call LTO bootstrap a new feature ;) Richard. > > -- > H.J.
