[Bug lto/115223] New: [15 regression] ICE when building KDE kontrast with LTO (error: ‘TYPE_CANONICAL’ has different ‘TYPE_CANONICAL’)

["sjames at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115223

            Bug ID: 115223
           Summary: [15 regression] ICE when building KDE kontrast with
                    LTO (error: ‘TYPE_CANONICAL’ has different
                    ‘TYPE_CANONICAL’)
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sjames at gcc dot gnu.org
  Target Milestone: ---

Created attachment 58284
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58284&action=edit
kontrast.cpp.ii.xz

This is different from the earlier bugs the other week. I hit a bunch of these
and just picked Kontrast at random.

```
# g++ -c -std=gnu++20 -flto kontrast.cpp.ii
In file included from
/var/tmp/portage/app-accessibility/kontrast-23.08.5/work/kontrast-23.08.5/src/kontrast.cpp:361:
/var/tmp/portage/app-accessibility/kontrast-23.08.5/work/kontrast-23.08.5_build/src/kontrast_autogen/include/moc_kontrast.cpp:356:27:
error: ‘TYPE_CANONICAL’ has different ‘TYPE_CANONICAL’
  356 | QT_WARNING_POP
      |                           ^
 <function_type 0xffff75afe000
    type <void_type 0xffff8084ff18 void type_6 VOID
        align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0xffff8084ff18
        pointer_to_this <pointer_type 0xffff80857000>>
    SI
    size <integer_cst 0xffff80846438 type <integer_type 0xffff8084f0a8
bitsizetype> constant 32>
    unit-size <integer_cst 0xffff80846450 type <integer_type 0xffff8084f000
sizetype> constant 4>
    align:32 warn_if_not_align:0 symtab:0 alias-set -1 structural-equality
    arg-types <tree_list 0xffff75af3aa0
        value <reference_type 0xffff72de99d8 type <record_type 0xffff72de77e0
QVariant>
            unsigned DI
            size <integer_cst 0xffff808461f8 constant 64>
            unit-size <integer_cst 0xffff80846210 constant 8>
            align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0xffff76cb8930>
        chain <tree_list 0xffff80838988 value <void_type 0xffff8084ff18 void>>>
    pointer_to_this <pointer_type 0xffff75afe0a8>>
 <function_type 0xffff73ab73f0
    type <void_type 0xffff7f128690 type type_6 VOID
        align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0xffff8084ff18>
    SI
    size <integer_cst 0xffff80846438 type <integer_type 0xffff8084f0a8
bitsizetype> constant 32>
    unit-size <integer_cst 0xffff80846450 type <integer_type 0xffff8084f000
sizetype> constant 4>
    align:32 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0xffff75afe000
    arg-types <tree_list 0xffff75af3aa0
        value <reference_type 0xffff72de99d8 type <record_type 0xffff72de77e0
QVariant>
            unsigned DI
            size <integer_cst 0xffff808461f8 constant 64>
            unit-size <integer_cst 0xffff80846210 constant 8>
            align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0xffff76cb8930>
        chain <tree_list 0xffff80838988 value <void_type 0xffff8084ff18 void>>>
    pointer_to_this <pointer_type 0xffff73ab7498>>
during IPA pass: *free_lang_data
/var/tmp/portage/app-accessibility/kontrast-23.08.5/work/kontrast-23.08.5_build/src/kontrast_autogen/include/moc_kontrast.cpp:356:27:
internal compiler error: ‘verify_type’ failed
0xaaaacbae3247 verify_type(tree_node const*)
        /usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree.cc:14434
0xaaaaccbd4523 free_lang_data
       
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/ipa-free-lang-data.cc:1134
0xaaaaccbd4523 execute
       
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/ipa-free-lang-data.cc:1176
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://bugs.gentoo.org/> for instructions.
```

```
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/aarch64-unknown-linux-gnu/15/lto-wrapper
Target: aarch64-unknown-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-15.0.9999/work/gcc-15.0.9999/configure
--host=aarch64-unknown-linux-gnu --build=aarch64-unknown-linux-gnu
--prefix=/usr --bindir=/usr/aarch64-unknown-linux-gnu/gcc-bin/15
--includedir=/usr/lib/gcc/aarch64-unknown-linux-gnu/15/include
--datadir=/usr/share/gcc-data/aarch64-unknown-linux-gnu/15
--mandir=/usr/share/gcc-data/aarch64-unknown-linux-gnu/15/man
--infodir=/usr/share/gcc-data/aarch64-unknown-linux-gnu/15/info
--with-gxx-include-dir=/usr/lib/gcc/aarch64-unknown-linux-gnu/15/include/g++-v15
--disable-silent-rules --disable-dependency-tracking
--with-python-dir=/share/gcc-data/aarch64-unknown-linux-gnu/15/python
--enable-languages=c,c++,fortran --enable-obsolete --enable-secureplt
--disable-werror --with-system-zlib --enable-nls --without-included-gettext
--disable-libunwind-exceptions --enable-checking=yes,extra,rtl
--with-bugurl=https://bugs.gentoo.org/ --with-pkgversion='Gentoo Hardened
15.0.9999 p, commit bc7d81fe2f725b4043ce8b9ffb11d80032ce3f75'
--with-gcc-major-version-only --enable-libstdcxx-time --enable-lto
--disable-libstdcxx-pch --enable-shared --enable-threads=posix
--enable-__cxa_atexit --enable-clocale=gnu --disable-multilib
--disable-fixed-point --enable-libgomp --disable-libssp --disable-libada
--disable-standard-branch-protection --disable-systemtap
--disable-valgrind-annotations --disable-vtable-verify --disable-libvtv
--with-zstd --without-isl --enable-default-pie --enable-host-pie
--enable-host-bind-now --enable-default-ssp --disable-fixincludes
--with-build-config=bootstrap-O3
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 15.0.0 20240523 (experimental)
ed63cd2aa5b114565fe5499c3a6bf8da5e8e48ba (Gentoo Hardened 15.0.9999 p, commit
bc7d81fe2f725b4043ce8b9ffb11d80032ce3f75)
```