[Bug middle-end/112619] New: [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57)

[Bug middle-end/112619] New: [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57)

[sjames at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

            Bug ID: 112619
           Summary: [14 regression] ICE when building libcrafter (tree
                    check: expected statement_list, have modify_expr in
                    tsi_start, at tree-iterator.h:57)
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sjames at gcc dot gnu.org
  Target Milestone: ---

Created attachment 56640
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56640&action=edit
ICMPCraft.ii

Originally reported downstream in Gentoo at https://bugs.gentoo.org/917592 by
Toralf Förster.

```
libtool: compile:  x86_64-pc-linux-gnu-g++ -DHAVE_CONFIG_H -I.
-I/usr/include/dbus-1.0 -I/usr/lib64/dbus-1.0/include -ansi -pedantic -Wall -O2
-march=native -pipe -fcf-protection=none -fdiagnostics-color=always
-fdiagnostics-urls=never -frecord-gcc-switches -ggdb3 -c
crafter/Protocols/ICMPCraft.cpp  -fPIC -DPIC -o
crafter/Protocols/.libs/ICMPCraft.o
In file included from crafter/Protocols/ICMP.h:30,
                 from crafter/Protocols/ICMPCraft.cpp:34:
crafter/Protocols/../Layer.h:246:32: warning: 'virtual Crafter::Layer&
Crafter::Layer::operator=(const Crafter::Layer&)' was hidden
[-Woverloaded-virtual=]
  246 |                 virtual Layer& operator=(const Layer& right);
      |                                ^~~~~~~~
In file included from crafter/Protocols/ICMP.h:31:
crafter/Protocols/ICMPLayer.h:15:15: note:   by 'Crafter::ICMPLayer&
Crafter::ICMPLayer::operator=(const Crafter::ICMPLayer&)'
   15 |         class ICMPLayer: public Layer {
      |               ^~~~~~~~~
crafter/Protocols/../Layer.h:246:32: warning: 'virtual Crafter::Layer&
Crafter::Layer::operator=(const Crafter::Layer&)' was hidden
[-Woverloaded-virtual=]
  246 |                 virtual Layer& operator=(const Layer& right);
      |                                ^~~~~~~~
crafter/Protocols/ICMP.h:35:11: note:   by 'Crafter::ICMP&
Crafter::ICMP::operator=(const Crafter::ICMP&)'
   35 |     class ICMP: public ICMPLayer {
      |           ^~~~
crafter/Protocols/ICMPCraft.cpp: In member function 'virtual std::string
Crafter::ICMP::MatchFilter() const':
crafter/Protocols/ICMPCraft.cpp:196:9: internal compiler error: tree check:
expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57
  196 |         if ( type == EchoRequest || type == TimeStampRequest ||
      |         ^~
0x55b58f7d2432 tree_check_failed(tree_node const*, char const*, int, char
const*, ...)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/tree.cc:8952
0x55b58e6c2423 tree_check(tree_node*, char const*, int, char const*, tree_code)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/tree.h:3602
0x55b58e6c2423 tsi_start(tree_node*)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/tree-iterator.h:57
0x55b58ea0a100 try_catch_may_fallthru
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/tree.cc:12576
0x55b58ea0a100 block_may_fallthru(tree_node const*)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/tree.cc:12649
0x55b59092bac0 block_may_fallthru(tree_node const*)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/tree.cc:12659
0x55b59092b20a shortcut_cond_expr
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:4412
0x55b59090c794 gimplify_cond_expr
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:4691
0x55b5900af22a gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:16672
0x55b5900ad2f0 gimplify_stmt(tree_node**, gimple**)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:7472
0x55b5908f2131 gimplify_bind_expr
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:1614
0x55b5900af3aa gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:16916
0x55b5900af2b9 gimplify_stmt(tree_node**, gimple**)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:7472
0x55b5900af2b9 gimplify_statement_list
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:2222
0x55b5900af2b9 gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:17160
0x55b5900ad2f0 gimplify_stmt(tree_node**, gimple**)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:7472
0x55b5900aec7a gimplify_and_add(tree_node*, gimple**)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:493
0x55b5900aec7a gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:17067
0x55b5900af2b9 gimplify_stmt(tree_node**, gimple**)
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:7472
0x55b5900af2b9 gimplify_statement_list
       
/usr/src/debug/sys-devel/gcc-14.0.0.9999/gcc-14.0.0.9999/gcc/gimplify.cc:2222
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/x86_64-pc-linux-gnu/14/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-14.0.0.9999/work/gcc-14.0.0.9999/configure
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --prefix=/usr
--bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/14
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/14/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/14
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/14/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/14/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/14/include/g++-v14
--disable-silent-rules --disable-dependency-tracking
--with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/14/python
--enable-languages=c,c++,fortran,rust --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
14.0.0 p, commit 35bb529f420ff5863fdae51049e6935ab927ff3d'
--with-gcc-major-version-only --enable-libstdcxx-time --enable-lto
--disable-libstdcxx-pch --enable-shared --enable-threads=posix
--enable-__cxa_atexit --enable-clocale=gnu --enable-multilib
--with-multilib-list=m32,m64 --disable-fixed-point --enable-targets=all
--enable-libgomp --disable-libssp --disable-libada --enable-cet
--disable-systemtap --enable-valgrind-annotations --disable-vtable-verify
--disable-libvtv --with-zstd --with-isl --disable-isl-version-check
--enable-default-pie --enable-host-pie --enable-host-bind-now
--enable-default-ssp --with-build-config='bootstrap-O3 bootstrap-lto
bootstrap-cet'
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 14.0.0 20231118 (experimental)
841008d3966c0fe7a80ec10703a50fbdab7620ac (Gentoo Hardened 14.0.0 p, commit
35bb529f420ff5863fdae51049e6935ab927ff3d)
```

Needs 'g++ -c ICMPCraft.ii -ansi'.

[Bug middle-end/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57)

[kocelfc at tutanota dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

Kostadin Shishmanov <kocelfc at tutanota dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |kocelfc at tutanota dot com

--- Comment #1 from Kostadin Shishmanov <kocelfc at tutanota dot com> ---
reduction:


struct basic_string {
  basic_string(const char *);
  ~basic_string();
};
char InformationRequest, AddressMaskRequest;
struct ICMP {
  basic_string MatchFilter() const;
};
basic_string ICMP::MatchFilter() const {
  if (InformationRequest || AddressMaskRequest) {
    basic_string ret_string = "";
    return ret_string;
  }
  return "";
}

[Bug middle-end/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57)

[kocelfc at tutanota dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

Kostadin Shishmanov <kocelfc at tutanota dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at redhat dot com

--- Comment #2 from Kostadin Shishmanov <kocelfc at tutanota dot com> ---
Bisected to r14-5086-gae07265381d934

[Bug c++/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57) since r14-5086-gae07265381d934

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0
                 CC|                            |pinskia at gcc dot gnu.org

[Bug c++/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57) since r14-5086-gae07265381d934

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2023-11-19
     Ever confirmed|0                           |1

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed, -std=c++98 is enough to reproduce the ICE.

Slightly more reduced:
```
struct st1 {
  st1();
  ~st1();
};
st1 MatchFilter(char n, char b)  {
  if (n || b) {
    st1 ret_string;
    return ret_string;
  }
  return st1();
}
```

[Bug c++/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57) since r14-5086-gae07265381d934

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

[Bug c++/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57) since r14-5086-gae07265381d934

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

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

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

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
The created TRY_CATCH_EXPR certainly violates the try_catch_may_fallthrough
expectations, that the second operand of TRY_CATCH_EXPR is a STATEMENT_LIST,
which either a series of CATCH_EXPRs, or containing EH_FILTER_EXPR, or
statements
ending with RESX.  In this case the second operand is just MODIFY_EXPR.
So, shall we change try_catch_may_fallthrough to accept that as well and just
return false if second argument is not a STATEMENT_LIST, or handle such case as
if a single statement STATEMENT_LIST, something else?

[Bug c++/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57) since r14-5086-gae07265381d934

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 56663
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56663&action=edit
gcc14-pr112619.patch

If it is ok for TRY_CATCH_EXPR to have second argument be something other than
STATEMENT_LIST, then this patch seems to work (and handles those cases like a
STATEMENT_LIST containing a single statement).

[Bug c++/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57) since r14-5086-gae07265381d934

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:1c44bd92a86db3fcdeb4a66ce2f3222d13af0681

commit r14-5814-g1c44bd92a86db3fcdeb4a66ce2f3222d13af0681
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Nov 24 08:44:28 2023 +0100

    tree: Fix up try_catch_may_fallthru [PR112619]

    The following testcase ICEs with -std=c++98 since r14-5086 because
    block_may_fallthru is called on a TRY_CATCH_EXPR whose second operand
    is a MODIFY_EXPR rather than STATEMENT_LIST, which try_catch_may_fallthru
    apparently expects.
    I've been wondering whether that isn't some kind of FE bug and whether
    there isn't some unwritten rule that second operand of TRY_CATCH_EXPR
    must be a STATEMENT_LIST.  Looking at the FEs, the C++ FE uses mostly its
    own trees, TRY_BLOCK (TRY_CATCH_EXPR replacement) with HANDLER in it
(CATCH_EXPR
    replacement) - but HANDLER can be immediate second operand rather than
nested
    in STATEMENT_LIST, EH_SPEC_BLOCK (this one stands for both TRY_CATCH_EXPR
    and EH_FILTER_EXPR in its second argument); both of these are only replaced
    by the generic trees during gimplification though, so will unlikely be seen
    by block_may_fallthru; and then CLEANUP_STMT, which is genericized
    into TRY_CATCH_EXPR with non-CATCH_EXPR/EH_FILTER_EXPR in its body (this is
    the one that causes the ICE on this testcase).
    The Go and Rust FEs create TRY_CATCH_EXPR with CATCH_EXPR immediately in
its
    second argument (but either are unlucky that block_may_fallthru isn't
called
    or the body can always fallthru, or latent ICE), while the D FE most likely
    hit this ICE and attempts to work around it, by checking at TRY_CATCH_EXPR
    creation time if the second argument from pop_stmt_list is STATEMENT_LIST
and
    if not, forcefully wraps it into a STATEMENT_LIST.

    Unfortunately, I don't see an easy way to create an artificial tree
iterator
    from just a single tree statement, so the patch duplicates what the loops
    later do (after all, it is very simple, just didn't want to duplicate
    also the large comments explaning it, so the 3 See below. comments).

    2023-11-24  Jakub Jelinek  <jakub@redhat.com>

            PR c++/112619
            * tree.cc (try_catch_may_fallthru): If second operand of
            TRY_CATCH_EXPR is not a STATEMENT_LIST, handle it as if it was a
            STATEMENT_LIST containing a single statement.

            * g++.dg/eh/pr112619.C: New test.

[Bug c++/112619] [14 regression] ICE when building libcrafter (tree check: expected statement_list, have modify_expr in tsi_start, at tree-iterator.h:57) since r14-5086-gae07265381d934

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112619

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

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

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Should be fixed now.