[Bug c++/100441] New: [ICE] output_constant_pool_2, at varasm.c:3955

[Bug c++/100441] New: [ICE] output_constant_pool_2, at varasm.c:3955

[tim at klingt dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

            Bug ID: 100441
           Summary: [ICE] output_constant_pool_2, at varasm.c:3955
           Product: gcc
           Version: 10.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tim at klingt dot org
  Target Milestone: ---

Created attachment 50762
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50762&action=edit
reduced testcase

i came across an ICE that appears when compiling for arch64 and optimisations
enabled.

```
➜  dev /path/to/sdk/usr/bin/aarch64-poky-linux/aarch64-poky-linux-g++ -S -O
testcase2.i -fpermissive -w
testcase2.i:43:1: internal compiler error: in output_constant_pool_2, at
varasm.c:3955
   43 | } // namespace a
      | ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <https://gcc.gnu.org/bugs/> for instructions.
➜  dev /path/to/sdk/usr/bin/aarch64-poky-linux/aarch64-poky-linux-g++ -S
testcase2.i -fpermissive -w
➜  dev
➜  dev /path/to/sdk/usr/bin/aarch64-poky-linux/aarch64-poky-linux-g++ --version 
aarch64-poky-linux-g++ (GCC) 9.2.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
```

reduced test-case is attached. could reproduce the issue with gcc-9.2, 9.3 and
10.2

[Bug target/100441] [ICE] output_constant_pool_2, at varasm.c:3955

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |aarch64
           Keywords|                            |ice-on-valid-code
      Known to fail|                            |10.2.0, 9.2.0, 9.3.0
          Component|c++                         |target

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Can you share how the compiler was configured?  It says so when you run the
failing compile with -v

A quick try with a cross from x86_64 on trunk doesn't reproduce the issue.

[Bug target/100441] [ICE] output_constant_pool_2, at varasm.c:3955

[tim at klingt dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

--- Comment #2 from tim blechmann <tim at klingt dot org> ---
i've been able to reproduce this on a raspberry pi running ubuntu:


```
ubuntu@pi4:~/scratch$ g++-10 x.i -S -fpermissive -w -O -v
Using built-in specs.
COLLECT_GCC=g++-10
Target: aarch64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu
10.2.0-5ubuntu1~20.04' --with-bugurl=file:///usr/share/doc/gcc-10/README.Bugs
--enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++,m2 --prefix=/usr
--with-gcc-major-version-only --program-suffix=-10
--program-prefix=aarch64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new
--enable-gnu-unique-object --disable-libquadmath --disable-libquadmath-support
--enable-plugin --enable-default-pie --with-system-zlib
--enable-libphobos-checking=release --with-target-system-zlib=auto
--enable-objc-gc=auto --enable-multiarch --enable-fix-cortex-a53-843419
--disable-werror --enable-checking=release --build=aarch64-linux-gnu
--host=aarch64-linux-gnu --target=aarch64-linux-gnu
Thread model: posix
```

i've also seen this with a yocto toolchain:
```
Configured with: ../../../../../../work-shared/gcc-9.2.0-r0/gcc-9.2.0/configure
--build=x86_64-linux --host=x86_64-yoctosdk-linux --target=aarch64-poky-linux
--prefix=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr
--exec_prefix=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr
--bindir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/bin/aarch64-poky-linux
--sbindir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/bin/aarch64-poky-linux
--libexecdir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/libexec/aarch64-poky-linux
--datadir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/share
--sysconfdir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/etc
--sharedstatedir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/com
--localstatedir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/var
--libdir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/lib/aarch64-poky-linux
--includedir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/include
--oldincludedir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/include
--infodir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/share/info
--mandir=/opt/Yocto/1.2.0/sysroots/x86_64-yoctosdk-linux/usr/share/man
--disable-silent-rules --disable-dependency-tracking
--with-libtool-sysroot=/var/build/bamboo-build/tmp/work/x86_64-nativesdk-yoctosdk-linux/gcc-cross-canadian-aarch64/9.2.0-r0/recipe-sysroot
--with-gnu-ld --enable-shared --enable-languages=c,c++ --enable-threads=posix
--enable-multilib --enable-default-pie --enable-c99 --enable-long-long
--enable-symvers=gnu --enable-libstdcxx-pch
--program-prefix=aarch64-poky-linux- --without-local-prefix --enable-lto
--disable-libssp --enable-libitm --disable-bootstrap --disable-libmudflap
--with-system-zlib --with-linker-hash-style=gnu --enable-linker-build-id
--with-ppl=no --with-cloog=no --enable-checking=release
--enable-cheaders=c_global --without-isl
--with-gxx-include-dir=/not/exist/usr/include/c++/9.2.0
--with-build-time-tools=/var/build/bamboo-build/tmp/work/x86_64-nativesdk-yoctosdk-linux/gcc-cross-canadian-aarch64/9.2.0-r0/recipe-sysroot-native/usr/aarch64-poky-linux/bin
--with-sysroot=/not/exist
--with-build-sysroot=/var/build/bamboo-build/tmp/work/x86_64-nativesdk-yoctosdk-linux/gcc-cross-canadian-aarch64/9.2.0-r0/recipe-sysroot
--enable-poison-system-directories --disable-static --enable-nls
--with-glibc-version=2.28 --enable-initfini-array --enable-__cxa_atexit
Thread model: posix
gcc version 9.2.0 (GCC) 
```
alternative configuration

[Bug target/100441] [ICE] output_constant_pool_2, at varasm.c:3955

[acoplan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

Alex Coplan <acoplan at gcc dot gnu.org> changed:

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

--- Comment #3 from Alex Coplan <acoplan at gcc dot gnu.org> ---
I can reproduce it on the GCC 9 branch but nowhere else (not on 10, 11, or
trunk).

[Bug target/100441] [ICE] output_constant_pool_2, at varasm.c:3955

[acoplan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

Alex Coplan <acoplan at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
                 CC|                            |jakub at gcc dot gnu.org
   Last reconfirmed|                            |2021-05-06

--- Comment #4 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Hmm, a bisect between basepoints/gcc-10 and master shows that it stopped ICEing
with r11-2944-g0106300f6c3f7bae5eb1c46dbd45aa07c94e1b15.

Confirmed on the GCC 9 branch. I guess we need to determine whether Jakub's
commit above fixes the bug or just hides it.

[Bug target/100441] [ICE] output_constant_pool_2, at varasm.c:3955

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
My patch was an optimization, certainly not an attempt to fix any bugs.
So I bet the bug is now latent.

[Bug target/100441] [ICE] output_constant_pool_2, at varasm.c:3955

[acoplan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

--- Comment #6 from Alex Coplan <acoplan at gcc dot gnu.org> ---
On the GCC 10 branch it was the backport of the PR99037 fix which stopped the
ICE (r11-7888-g37d9074e12082132ae62c12fbe958c697f638c0a on trunk,
r10-9628-g1a92899b08e61d503a2897f2f66b064eb84706bc on the branch).

[Bug target/100441] [ICE] output_constant_pool_2, at varasm.c:3955

[acoplan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

--- Comment #7 from Alex Coplan <acoplan at gcc dot gnu.org> ---
So I'd guess the PR99037 fix just needs backporting to GCC 9, but we'll need to
confirm that it's the same issue.

[Bug target/100441] [8/9 Regression] ICE in output_constant_pool_2, at varasm.c:3955

[acoplan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

Alex Coplan <acoplan at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[ICE]                       |[8/9 Regression] ICE in
                   |output_constant_pool_2, at  |output_constant_pool_2, at
                   |varasm.c:3955               |varasm.c:3955

--- Comment #8 from Alex Coplan <acoplan at gcc dot gnu.org> ---
GCC 8 also seems to be affected.

[Bug target/100441] [8/9 Regression] ICE in output_constant_pool_2, at varasm.c:3955

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

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

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

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Note, the 8 branch will be frozen tomorrow and closed in a week after that, so
if you have anything to backport there, please do that before noon CET May 7th.

[Bug target/100441] [8/9 Regression] ICE in output_constant_pool_2, at varasm.c:3955

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

--- Comment #10 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-9 branch has been updated by Kyrylo Tkachov
<ktkachov@gcc.gnu.org>:

https://gcc.gnu.org/g:3a9504e1f03bc2980062dc62261212e8635bcf93

commit r9-9519-g3a9504e1f03bc2980062dc62261212e8635bcf93
Author: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date:   Fri May 7 11:35:29 2021 +0100

    aarch64: PR target/99037 Fix RTL represntation in move_lo_quad patterns

    This patch fixes the RTL representation of the move_lo_quad patterns to use
aarch64_simd_or_scalar_imm_zero
    for the zero part rather than a vec_duplicate of zero or a const_int 0.
    The expander that generates them is also adjusted so that we use and match
the correct const_vector forms throughout.

    Co-Authored-By: Jakub Jelinek <jakub@redhat.com>
    gcc/ChangeLog:

            PR target/99037
            PR target/100441
            * config/aarch64/aarch64-simd.md (move_lo_quad_internal_<mode>):
Use
            aarch64_simd_or_scalar_imm_zero to match zeroes.  Remove pattern
            matching const_int 0.
            (move_lo_quad_internal_be_<mode>): Likewise.
            (move_lo_quad_<mode>): Update for the above.
            * config/aarch64/iterators.md (VQ_2E): Delete.

    gcc/testsuite/ChangeLog:

            PR target/99808
            * gcc.target/aarch64/pr99808.c: New test.

[Bug target/100441] [8/9 Regression] ICE in output_constant_pool_2, at varasm.c:3955

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

--- Comment #11 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-8 branch has been updated by Kyrylo Tkachov
<ktkachov@gcc.gnu.org>:

https://gcc.gnu.org/g:64b6b1d1bc796a7fea189a4c4b0e290540f51ae3

commit r8-10956-g64b6b1d1bc796a7fea189a4c4b0e290540f51ae3
Author: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date:   Fri May 7 11:36:54 2021 +0100

    aarch64: PR target/99037 Fix RTL represntation in move_lo_quad patterns

    This patch fixes the RTL representation of the move_lo_quad patterns to use
aarch64_simd_or_scalar_imm_zero
    for the zero part rather than a vec_duplicate of zero or a const_int 0.
    The expander that generates them is also adjusted so that we use and match
the correct const_vector forms throughout.

    Co-Authored-By: Jakub Jelinek <jakub@redhat.com>
    gcc/ChangeLog:

            PR target/99037
            PR target/100441
            * config/aarch64/aarch64-simd.md (move_lo_quad_internal_<mode>):
Use
            aarch64_simd_or_scalar_imm_zero to match zeroes.  Remove pattern
            matching const_int 0.
            (move_lo_quad_internal_be_<mode>): Likewise.
            (move_lo_quad_<mode>): Update for the above.
            * config/aarch64/iterators.md (VQ_2E): Delete.

    gcc/testsuite/ChangeLog:

            PR target/99808
            * gcc.target/aarch64/pr99808.c: New test.

[Bug target/100441] [8/9 Regression] ICE in output_constant_pool_2, at varasm.c:3955

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

--- Comment #12 from ktkachov at gcc dot gnu.org ---
Should be fixed on GCC 8 and 9 branches now?

[Bug target/100441] [8/9 Regression] ICE in output_constant_pool_2, at varasm.c:3955

[acoplan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

Alex Coplan <acoplan at gcc dot gnu.org> changed:

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

--- Comment #13 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Thanks Kyrill, I can confirm it's fixed on the 8 and 9 branches for the reduced
testcase.

[Bug target/100441] [8/9 Regression] ICE in output_constant_pool_2, at varasm.c:3955

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100441

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |8.5