[Bug bootstrap/95413] New: [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[Bug bootstrap/95413] New: [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[ro at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

            Bug ID: 95413
           Summary: [11 regression] i686-linux --enable-targets=all cannot
                    configure m64 libgomp
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ro at gcc dot gnu.org
                CC: hjl at gcc dot gnu.org
  Target Milestone: ---
            Target: i686-pc-linux-gnu

Between 20200515 and 20200522, Linux/i686 bootstrap with --enable-targets=all
broke: after configuring with

$ .../configure CC='gcc -m32' CXX='g++ -m32' --enable-targets=all
--enable-languages=c --build=i686-pc-linux-gnu --disable-lto-plugin

configuring the stage1 64-bit libgomp fails:

checking whether the C compiler works... no
configure: error: in
`/var/gcc/gcc-11.0.0-20200529/4.20.4-gcc-32/i686-pc-linux-gnu/64/libgomp':
configure: error: C compiler cannot create executables
See `config.log' for more details
make[2]: *** [Makefile:20360: configure-stage1-target-libgomp] Error 1

config.log has

configure:3935:
/var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/xgcc
-B/var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/
-B/vol/gcc/i686-pc-linux-gnu/bin/ -B/vol/gcc/i686-pc-linux-gnu/lib/ -isystem
/vol/gcc/i686-pc-linux-gnu/include -isystem
/vol/gcc/i686-pc-linux-gnu/sys-include -fno-checking  -m64 -g -O2 -pthread 
-Wall -Werror -ftls-model=initial-exec -DUSING_INITIAL_EXEC_TLS -march=i486
-mtune=i686   conftest.c  >&5
cc1: error: CPU you selected does not support x86-64 instruction set

whereas before this was

configure:3913: checking whether the C compiler works
configure:3935:
/var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/xgcc
-B/var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/
-B/vol/gcc/i686-pc-linux-gnu/bin/ -B/vol/gcc/i686-pc-linux-gnu/lib/ -isystem
/vol/gcc/i686-pc-linux-gnu/include -isystem
/vol/gcc/i686-pc-linux-gnu/sys-include -fno-checking  -m64 -g -O2 -pthread  
conftest.c  >&5

I strongly suspect the CET patches, but haven't yet figured out what's going
wrong.

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[ro at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

Rainer Orth <ro at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |11.0

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hjl.tools at gmail dot com
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2020-05-29
     Ever confirmed|0                           |1

--- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Rainer Orth from comment #0)
> Between 20200515 and 20200522, Linux/i686 bootstrap with --enable-targets=all
> broke: after configuring with
> 
> $ .../configure CC='gcc -m32' CXX='g++ -m32' --enable-targets=all
> --enable-languages=c --build=i686-pc-linux-gnu --disable-lto-plugin
> 
> configuring the stage1 64-bit libgomp fails:
> 
> checking whether the C compiler works... no
> configure: error: in
> `/var/gcc/gcc-11.0.0-20200529/4.20.4-gcc-32/i686-pc-linux-gnu/64/libgomp':
> configure: error: C compiler cannot create executables
> See `config.log' for more details
> make[2]: *** [Makefile:20360: configure-stage1-target-libgomp] Error 1
> 
> config.log has
> 
> configure:3935:
> /var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/xgcc
> -B/var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/
> -B/vol/gcc/i686-pc-linux-gnu/bin/ -B/vol/gcc/i686-pc-linux-gnu/lib/ -isystem
> /vol/gcc/i686-pc-linux-gnu/include -isystem
> /vol/gcc/i686-pc-linux-gnu/sys-include -fno-checking  -m64 -g -O2 -pthread 
> -Wall -Werror -ftls-model=initial-exec -DUSING_INITIAL_EXEC_TLS -march=i486
> -mtune=i686   conftest.c  >&5
> cc1: error: CPU you selected does not support x86-64 instruction set
> 
> whereas before this was
> 
> configure:3913: checking whether the C compiler works
> configure:3935:
> /var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/xgcc
> -B/var/gcc/regression/master/4.20.4-gcc-gas-gld-32/build/./gcc/
> -B/vol/gcc/i686-pc-linux-gnu/bin/ -B/vol/gcc/i686-pc-linux-gnu/lib/ -isystem
> /vol/gcc/i686-pc-linux-gnu/include -isystem
> /vol/gcc/i686-pc-linux-gnu/sys-include -fno-checking  -m64 -g -O2 -pthread  
> conftest.c  >&5
> 
> I strongly suspect the CET patches, but haven't yet figured out what's going
> wrong.

How did CET changes add -march=i486 -mtune=i686? Can you bisect to the commit?

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[ro at CeBiTec dot Uni-Bielefeld.DE]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

--- Comment #2 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> ---
> How did CET changes add -march=i486 -mtune=i686? Can you bisect to the commit?

Done: the reghunt identified

commit 4c1a5d8b71e29b71e0bc1004480c12c5fc427cb7
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri May 15 09:06:50 2020 -0700

    x86: Also check if -fcf-protection works

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> ---
I successfully bootstrapped

commit c92716b2b1d117a803775a2e2336b751050ff7c2
Author: Martin Liska <mliska@suse.cz>
Date:   Fri May 29 13:21:41 2020 +0200

    Port bugzilla-close-candidate script to git.

with

CC="cc -m32 -fno-lto" CXX="g++ -m32 -fno-lto"
RUNTESTFLAGS="--target_board='unix'"
/export/gnu/import/git/gitlab/x86-gcc/configure --enable-targets=all
--disable-lto-plugin --disable-libcc1 --disable-libsanitizer --enable-cet
--with-demangler-in-ld i686-linux --prefix=/usr/gcc-11.0.0-32bit
--with-local-prefix=/usr/local --enable-gnu-indirect-function
--enable-clocale=gnu --with-system-zlib --with-target-system-zlib
--with-fpmath=sse --enable-libmpx --enable-languages=c,c++
configure: WARNING: you should use --build, --host, --target
checking build system type... i686-pc-linux-gnu
checking host system type... i686-pc-linux-gnu
checking target system type... i686-pc-linux-gnu

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to ro@CeBiTec.Uni-Bielefeld.DE from comment #2)
> > How did CET changes add -march=i486 -mtune=i686? Can you bisect to the commit?
> 
> Done: the reghunt identified
> 
> commit 4c1a5d8b71e29b71e0bc1004480c12c5fc427cb7
> Author: H.J. Lu <hjl.tools@gmail.com>
> Date:   Fri May 15 09:06:50 2020 -0700
> 
>     x86: Also check if -fcf-protection works

I can't reproduce it.

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW
           Assignee|unassigned at gcc dot gnu.org      |hjl.tools at gmail dot com

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to H.J. Lu from comment #1)
> > I strongly suspect the CET patches, but haven't yet figured out what's going
> > wrong.
> 
> How did CET changes add -march=i486 -mtune=i686? Can you bisect to the
> commit?

-march=i486 -mtune=i686 is something added by libgomp/configure.tgt:
    # Note that bare i386 is not included here.  We need cmpxchg.
    i[456]86-*-linux*)
        config_path="linux/x86 linux posix"
        case " ${CC} ${CFLAGS} " in
          *" -m64 "*|*" -mx32 "*)
            ;;
          *)
            if test -z "$with_arch"; then
              XCFLAGS="${XCFLAGS} -march=i486 -mtune=${target_cpu}"
            fi
        esac
        ;;
But that should enable it only when building the 32-bit libgomp and not 32-bit.
 So something else must be adding -m64 somewhere later.

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

--- Comment #6 from H.J. Lu <hjl.tools at gmail dot com> ---
I am testing this:

diff --git a/config/cet.m4 b/config/cet.m4
index 2bb2c8a95ac..911fbd46475 100644
--- a/config/cet.m4
+++ b/config/cet.m4
@@ -7,13 +7,14 @@ GCC_ENABLE(cet, auto, ,[enable Intel CET in target
libraries],
           permit yes|no|auto)
 AC_MSG_CHECKING([for CET support])

+# NB: Avoid nested save_CFLAGS and save_LDFLAGS.
 case "$host" in
   i[[34567]]86-*-linux* | x86_64-*-linux*)
     case "$enable_cet" in
       auto)
        # Check if target supports multi-byte NOPs
        # and if assembler supports CET insn.
-       save_CFLAGS="$CFLAGS"
+       cet_save_CFLAGS="$CFLAGS"
        CFLAGS="$CFLAGS -fcf-protection"
        AC_COMPILE_IFELSE(
         [AC_LANG_PROGRAM(
@@ -27,7 +28,7 @@ asm ("setssbsy");
          ])],
         [enable_cet=yes],
         [enable_cet=no])
-       CFLAGS="$save_CFLAGS"
+       CFLAGS="$cet_save_CFLAGS"
        ;;
       yes)
        # Check if assembler supports CET.
@@ -64,7 +65,7 @@ AC_MSG_CHECKING([for CET support])
 case "$host" in
   i[[34567]]86-*-linux* | x86_64-*-linux*)
     may_have_cet=yes
-    save_CFLAGS="$CFLAGS"
+    cet_save_CFLAGS="$CFLAGS"
     CFLAGS="$CFLAGS -fcf-protection"
     case "$enable_cet" in
       auto)
@@ -93,7 +94,7 @@ asm ("setssbsy");
         [AC_MSG_ERROR([assembler with CET support is required for
--enable-cet])])
        ;;
     esac
-    CFLAGS="$save_CFLAGS"
+    CFLAGS="$cet_save_CFLAGS"
     ;;
   *)
     may_have_cet=no
@@ -101,9 +102,9 @@ asm ("setssbsy");
     ;;
 esac

-save_CFLAGS="$CFLAGS"
+cet_save_CFLAGS="$CFLAGS"
 CFLAGS="$CFLAGS -fcf-protection=none"
-save_LDFLAGS="$LDFLAGS"
+cet_save_LDFLAGS="$LDFLAGS"
 LDFLAGS="$LDFLAGS -Wl,-z,ibt,-z,shstk"
 if test x$may_have_cet = xyes; then
   # Check whether -fcf-protection=none -Wl,-z,ibt,-z,shstk work.
@@ -159,6 +160,6 @@ if test x$enable_cet = xyes; then
 else
   AC_MSG_RESULT([no])
 fi
-CFLAGS="$save_CFLAGS"
-LDFLAGS="$save_LDFLAGS"
+CFLAGS="$cet_save_CFLAGS"
+LDFLAGS="$cet_save_LDFLAGS"
 ])

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[ro at CeBiTec dot Uni-Bielefeld.DE]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

--- Comment #7 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> ---
> --- Comment #6 from H.J. Lu <hjl.tools at gmail dot com> ---
> I am testing this:
[...]

Seems to work fine: at least configuring and building the 32 and 64-bit
libgomp multilibs now succeeds.

Thanks.
        Rainer

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |https://gcc.gnu.org/piperma
                   |                            |il/gcc-patches/2020-May/546
                   |                            |849.html
           Keywords|                            |patch

--- Comment #8 from H.J. Lu <hjl.tools at gmail dot com> ---
A patch is posted at

https://gcc.gnu.org/pipermail/gcc-patches/2020-May/546849.html

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by H.J. Lu <hjl@gcc.gnu.org>:

https://gcc.gnu.org/g:9051b548274bffef9f41e720e1894d12cf68a47c

commit r11-732-g9051b548274bffef9f41e720e1894d12cf68a47c
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri May 29 12:23:33 2020 -0700

    Avoid nested save_CFLAGS and save_LDFLAGS

    Avoid nested save_CFLAGS and save_LDFLAGS by replacing save_CFLAGS and
    save_LDFLAGS with cet_save_CFLAGS and cet_save_LDFLAGS in cet.m4.

    config/

            PR bootstrap/95413
            * cet.m4: Replace save_CFLAGS and save_LDFLAGS with
            cet_save_CFLAGS and cet_save_LDFLAGS.

    gcc/

            PR bootstrap/95413
            * configure: Regenerated.

    libatomic/

            PR bootstrap/95413
            * configure: Regenerated.

    libbacktrace/

            PR bootstrap/95413
            * configure: Regenerated.

    libcc1/

            PR bootstrap/95413
            * configure: Regenerated.

    libcpp/

            PR bootstrap/95413
            * configure: Regenerated.

    libdecnumber/

            PR bootstrap/95413
            * configure: Regenerated.

    libgcc/

            PR bootstrap/95413
            * configure: Regenerated.

    libgfortran/

            PR bootstrap/95413
            * configure: Regenerated.

    libgomp/

            PR bootstrap/95413
            * configure: Regenerated.

    libiberty/

            PR bootstrap/95413
            * configure: Regenerated.

    libitm/

            PR bootstrap/95413
            * configure: Regenerated.

    libobjc/

            PR bootstrap/95413
            * configure: Regenerated.

    libphobos/

            PR bootstrap/95413
            * configure: Regenerated.

    libquadmath/

            PR bootstrap/95413
            * configure: Regenerated.

    libsanitizer/

            PR bootstrap/95413
            * configure: Regenerated.

    libssp/

            PR bootstrap/95413
            * configure: Regenerated.

    libstdc++-v3/

            PR bootstrap/95413
            * configure: Regenerated.

    libvtv/

            PR bootstrap/95413
            * configure: Regenerated.

    lto-plugin/

            PR bootstrap/95413
            * configure: Regenerated.

    zlib/

            PR bootstrap/95413
            * configure: Regenerated.

[Bug bootstrap/95413] [11 regression] i686-linux --enable-targets=all cannot configure m64 libgomp

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95413

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|NEW                         |RESOLVED

--- Comment #10 from H.J. Lu <hjl.tools at gmail dot com> ---
Fixed.