[Bug rtl-optimization/113506] New: ICE: RTL check: expected elt 2 type 'B', have '0' (rtx barrier) in BLOCK_FOR_INSN, at rtl.h:1495 with -Os -fno-tree-coalesce-vars -finline-stringops

["zsojka at seznam dot cz" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113506

            Bug ID: 113506
           Summary: ICE: RTL check: expected elt 2 type 'B', have '0' (rtx
                    barrier) in BLOCK_FOR_INSN, at rtl.h:1495 with -Os
                    -fno-tree-coalesce-vars -finline-stringops
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: riscv64-unknown-linux-gnu

Created attachment 57161
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57161&action=edit
reduced testcase (from gcc.dg/torture/pr69886.c)

RTL checking might need to be enabled.

Compiler output:
$ riscv64-unknown-linux-gnu-gcc -Os -fno-tree-coalesce-vars -finline-stringops
testcase.c
during RTL pass: expand
testcase.c: In function 'foo':
testcase.c:12:1: internal compiler error: RTL check: expected elt 2 type 'B',
have '0' (rtx barrier) in BLOCK_FOR_INSN, at rtl.h:1495
   12 | }
      | ^
0xad3d4c rtl_check_failed_type1(rtx_def const*, int, int, char const*, int,
char const*)
        /repo/gcc-trunk/gcc/rtl.cc:751
0xa20a79 BLOCK_FOR_INSN(rtx_def*)
        /repo/gcc-trunk/gcc/rtl.h:1495
0xa242a6 BLOCK_FOR_INSN(rtx_def*)
        /repo/gcc-trunk/gcc/emit-rtl.cc:4384
0xa242a6 set_block_for_insn(rtx_insn*, basic_block_def*)
        /repo/gcc-trunk/gcc/rtl.h:1500
0xa242a6 add_insn_before(rtx_insn*, rtx_insn*, basic_block_def*)
        /repo/gcc-trunk/gcc/emit-rtl.cc:4379
0x127efd0 emit_pattern_before_noloc
        /repo/gcc-trunk/gcc/emit-rtl.cc:4647
0x11a0d04 commit_one_edge_insertion(edge_def*)
        /repo/gcc-trunk/gcc/cfgrtl.cc:2071
0x11a6011 commit_edge_insertions()
        /repo/gcc-trunk/gcc/cfgrtl.cc:2133
0x11866e0 execute
        /repo/gcc-trunk/gcc/cfgexpand.cc:6956
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

$ riscv64-unknown-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-riscv64/bin/riscv64-unknown-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r14-8284-20240119180625-g54519030b05-checking-yes-rtl-df-extra-riscv64/bin/../libexec/gcc/riscv64-unknown-linux-gnu/14.0.1/lto-wrapper
Target: riscv64-unknown-linux-gnu
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--with-cloog --with-ppl --with-isl --with-isa-spec=2.2
--with-sysroot=/usr/riscv64-unknown-linux-gnu --build=x86_64-pc-linux-gnu
--host=x86_64-pc-linux-gnu --target=riscv64-unknown-linux-gnu
--with-ld=/usr/bin/riscv64-unknown-linux-gnu-ld
--with-as=/usr/bin/riscv64-unknown-linux-gnu-as --disable-multilib
--disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-r14-8284-20240119180625-g54519030b05-checking-yes-rtl-df-extra-riscv64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 14.0.1 20240119 (experimental) (GCC)