https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120522
Bug ID: 120522 Summary: [16 Regression] RISC-V: Miscompile at -O3 since r16-449-gd884e9c5c74 Product: gcc Version: 16.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: ewlu at rivosinc dot com Target Milestone: --- Testcase: unsigned char a; long long ao; short g = 29461; unsigned i = 6; unsigned l = 8; char y[23]; unsigned char ac[23][23][23][23][23]; char aq[23][3]; char ar; void b(short g, unsigned i, unsigned l, char y[], unsigned char ac[][23][23][23][23]) { for (unsigned ag = 0; ag < 23; ag++) for (short ah = 0; ah < 3; ah = l) for (unsigned ai = 0; ai < 23; ai++) for (unsigned aj = 0; aj < y[ag] - 98; aj += 3) for (short ak = 0; ak < (short)(ac[ag][ah][6][ai][aj] + i); ak += g - 29460) a += 6; } int main() { for (int af = 0; af < 23; ++af) y[af] = 121; for (int af = 0; af < 23; ++af) for (int at = 0; at < 3; ++at) aq[0][at] = ar; b(g, i, l, y, ac); ao = a + 9; __builtin_printf("%llu\n", ao); } Commands # -O3 > /scratch/ewlu/daily-upstream-build/build-gcv/bin/riscv64-unknown-linux-gnu-gcc > -march=rv64gcv -flto -O3 red.c -o user-config.out -fsigned-char > -fno-strict-aliasing -fwrapv > QEMU_CPU=rv64,vlen=128,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve64f=true > timeout --verbose -k 0.1 4 > /scratch/ewlu/daily-upstream-build/build-gcv/bin/qemu-riscv64 user-config.out > 1 146 # -O2 > /scratch/ewlu/daily-upstream-build/build-gcv/bin/riscv64-unknown-linux-gnu-gcc > -march=rv64gcv -flto -O2 red.c -o user-config.out -fsigned-char > -fno-strict-aliasing -fwrapv > QEMU_CPU=rv64,vlen=128,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve64f=true > timeout --verbose -k 0.1 4 > /scratch/ewlu/daily-upstream-build/build-gcv/bin/qemu-riscv64 user-config.out > 1 41 Found via fuzzer