https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116202
Bug ID: 116202
Summary: RISC-V: Miscompile at -O3 with zvl256b
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: patrick at rivosinc dot com
Target Milestone: ---
Testcase:
int b[24];
_Bool c[24];
int main() {
for (int f = 0; f < 4; ++f)
b[f] = 6;
for (int f = 0; f < 24; f += 4)
c[f] = ({
int g = ({
unsigned long g = -b[f];
1 < g ? 1 : g;
});
g;
});
__builtin_printf("%u\n", c[0]);
}
Commands:
> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/riscv64-unknown-linux-gnu-gcc
> -march=rv64gcv_zvl256b -O3 red.c -o user-config.out -fsigned-char
> -fno-strict-aliasing -fwrapv
> QEMU_CPU=rv64,vlen=256,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve32x=true,zve64d=true,zve64f=true,zve64x=true
> timeout --verbose -k 0.1 4
> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/qemu-riscv64
> user-config.out
255
> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/riscv64-unknown-linux-gnu-gcc
> -march=rv64gcv_zvl256b -O2 red.c -o user-config.out -fsigned-char
> -fno-strict-aliasing -fwrapv
> QEMU_CPU=rv64,vlen=256,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve32x=true,zve64d=true,zve64f=true,zve64x=true
> timeout --verbose -k 0.1 4
> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/qemu-riscv64
> user-config.out
1
Found via fuzzer.
