https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127443
Bug ID: 127443
Summary: [17 Regression] ICE: in simplify_subreg_concatn, at
lower-subreg.cc:678 with -O -g
Product: gcc
Version: 17.0
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 65615
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=65615&action=edit
reduced testcase
Compiler output:
$ riscv64-unknown-linux-gnu-gcc -O -g -march=rv64gv -mabi=lp64d testcase.c
during RTL pass: subreg1
testcase.c: In function 'foo':
testcase.c:11:1: internal compiler error: in simplify_subreg_concatn, at
lower-subreg.cc:678
11 | }
| ^
0x3881d2d internal_error(char const*, ...)
/repo/gcc-trunk/gcc/diagnostic-global-context.cc:787
0x1183f7d fancy_abort(char const*, int, char const*)
/repo/gcc-trunk/gcc/diagnostics/context.cc:1813
0x115d424 simplify_subreg_concatn
/repo/gcc-trunk/gcc/lower-subreg.cc:678
0x370eeff resolve_debug
/repo/gcc-trunk/gcc/lower-subreg.cc:1261
0x370eeff decompose_multiword_subregs
/repo/gcc-trunk/gcc/lower-subreg.cc:1678
0x370f91a execute
/repo/gcc-trunk/gcc/lower-subreg.cc:1824
/repo/gcc-trunk/binary-trunk-20260916200900-r17-4373-gd9128914a30615-checking-yes-rtl-df-extra-riscv64/bin/../libexec/gcc/riscv64-unknown-linux-gnu/17.0.0/cc1
-quiet -imultilib . -iprefix
/repo/gcc-trunk/binary-trunk-20260916200900-r17-4373-gd9128914a30615-checking-yes-rtl-df-extra-riscv64/bin/../lib/gcc/riscv64-unknown-linux-gnu/17.0.0/
testcase.c -quiet -dumpdir a- -dumpbase testcase.c -dumpbase-ext .c
-march=rv64gv -mabi=lp64d -misa-spec=2.2 -mtls-dialect=trad
-march=rv64imafdv_zmmul_zaamo_zalrsc_zve32f_zve32x_zve64d_zve64f_zve64x_zvl128b_zvl32b_zvl64b
-g -O -o /tmp/ccVP2pVc.s
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-20260916200900-r17-4373-gd9128914a30615-checking-yes-rtl-df-extra-riscv64/bin/../libexec/gcc/riscv64-unknown-linux-gnu/17.0.0/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-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
--enable-libsanitizer --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-20260916200900-r17-4373-gd9128914a30615-checking-yes-rtl-df-extra-riscv64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 17.0.0 20260916 (experimental) (GCC)
