chore: upgrade rust-toolchain to nightly-2025-11-20

.github/workflows/lints.yml

@@ -25,7 +25,7 @@ jobs:
           components: rustfmt, clippy
           targets: riscv32im-unknown-none-elf
           # TODO: figure out way to keep this in sync with rust-toolchain.toml automatically
-          toolchain: nightly-2025-08-18
+          toolchain: nightly-2025-11-20
       - name: Cargo cache
         uses: actions/cache@v4
         with:

.github/workflows/tests.yml

@@ -24,7 +24,7 @@ jobs:
         with:
           targets: riscv32im-unknown-none-elf
           # TODO: figure out way to keep this in sync with rust-toolchain.toml automatically
-          toolchain: nightly-2025-08-18
+          toolchain: nightly-2025-11-20
       - name: Cargo cache
         uses: actions/cache@v4
         with:

ceno_cli/src/utils.rs

@@ -78,12 +78,13 @@ pub fn search_workspace_root<P: AsRef<Path>>(path: P) -> anyhow::Result<PathBuf>
 pub fn get_rust_flags() -> String {
     const BASE_RUST_FLAGS: &[&str] = &[
         "-C",
-        "panic=abort",
+        "panic=immediate-abort",
         "-C",
         "link-arg=-Tmemory.x",
         "-C",
         "link-arg=-Tceno_link.x",
         "-Zlocation-detail=none",
+        "-Zunstable-options",
         "-C",
         "passes=lower-atomic",
         "--cfg",
@@ -104,7 +105,7 @@ pub fn apply_cargo_build_std_args(command: &mut Command) {
         "-Z",
         "build-std=alloc,core,compiler_builtins,std,panic_abort,proc_macro",
         "-Z",
-        "build-std-features=compiler-builtins-mem,panic_immediate_abort,default",
+        "build-std-features=compiler-builtins-mem,default",
     ];
     command.args(BASE_CARGO_ARGS);
 }

ceno_rt/riscv32im-ceno-zkvm-elf.json

@@ -28,5 +28,5 @@
   "singlethread": true,
   "target-c-int-width": 32,
   "target-endian": "little",
-  "target-pointer-width": "32"
+  "target-pointer-width": 32
 }

ceno_zkvm/src/bin/bitwise_keccak.rs

@@ -1,5 +1,5 @@
 use ceno_zkvm::precompiles::{run_bitwise_keccakf, setup_bitwise_keccak_gkr_circuit};
-use clap::{Parser, command};
+use clap::Parser;
 use ff_ext::GoldilocksExt2;
 use itertools::Itertools;
 use mpcs::BasefoldDefault;

ceno_zkvm/src/bin/lookup_keccak.rs

@@ -1,5 +1,5 @@
 use ceno_zkvm::precompiles::{run_lookup_keccakf, setup_lookup_keccak_gkr_circuit};
-use clap::{Parser, command};
+use clap::Parser;
 use ff_ext::GoldilocksExt2;
 use itertools::Itertools;
 use mpcs::BasefoldDefault;

ceno_zkvm/src/precompiles/lookup_keccakf.rs

@@ -389,6 +389,7 @@ impl<E: ExtensionField> ProtocolBuilder<E> for KeccakLayout<E> {
         // iterator over split witnesses
         let mut rotation_witness = rotation_witness.iter();
 
+        #[allow(clippy::needless_range_loop)]
         for i in 0..5 {
             #[allow(clippy::needless_range_loop)]
             for j in 0..5 {

ceno_zkvm/src/scheme/mock_prover.rs

@@ -783,29 +783,27 @@ impl<'a, E: ExtensionField + Hash> MockProver<E> {
                     .collect();
 
                 // Count lookups infered from ConstraintSystem from all instances into lkm_from_cs.
-                for i in 0..selected_count {
+                for (arg0, arg1) in args_eval[0]
+                    .iter()
+                    .zip(args_eval[1].iter())
+                    .take(selected_count)
+                {
                     match rom_type {
                         ROMType::Dynamic => {
-                            lkm_from_cs.assert_dynamic_range(args_eval[0][i], args_eval[1][i]);
+                            lkm_from_cs.assert_dynamic_range(*arg0, *arg1);
                         }
                         ROMType::DoubleU8 => {
-                            lkm_from_cs.assert_double_u8(args_eval[0][i], args_eval[1][i]);
-                        }
-                        ROMType::And => {
-                            lkm_from_cs.lookup_and_byte(args_eval[0][i], args_eval[1][i])
-                        }
-                        ROMType::Or => lkm_from_cs.lookup_or_byte(args_eval[0][i], args_eval[1][i]),
-                        ROMType::Xor => {
-                            lkm_from_cs.lookup_xor_byte(args_eval[0][i], args_eval[1][i])
-                        }
-                        ROMType::Ltu => {
-                            lkm_from_cs.lookup_ltu_byte(args_eval[0][i], args_eval[1][i])
+                            lkm_from_cs.assert_double_u8(*arg0, *arg1);
                         }
+                        ROMType::And => lkm_from_cs.lookup_and_byte(*arg0, *arg1),
+                        ROMType::Or => lkm_from_cs.lookup_or_byte(*arg0, *arg1),
+                        ROMType::Xor => lkm_from_cs.lookup_xor_byte(*arg0, *arg1),
+                        ROMType::Ltu => lkm_from_cs.lookup_ltu_byte(*arg0, *arg1),
                         ROMType::Pow => {
-                            assert_eq!(args_eval[0][i], 2);
-                            lkm_from_cs.lookup_pow2(args_eval[1][i])
+                            assert_eq!(*arg0, 2);
+                            lkm_from_cs.lookup_pow2(*arg1)
                         }
-                        ROMType::Instruction => lkm_from_cs.fetch(args_eval[0][i] as u32),
+                        ROMType::Instruction => lkm_from_cs.fetch(*arg0 as u32),
                     };
                 }
             }

ceno_zkvm/src/uint/arithmetic.rs

@@ -798,7 +798,7 @@ mod tests {
 
         #[test]
         fn test_add_mul2() {
-            let witness_values: Vec<ArcMultilinearExtension<E>> = vec![
+            let witness_values: Vec<ArcMultilinearExtension<E>> = [
                 // alloc a = 1 + 1 * 2^16
                 vec![1, 1, 0, 0],
                 // alloc b = 2 + 1 * 2^16

examples/.cargo/config.toml

@@ -9,12 +9,15 @@ build-std = [
 ]
 build-std-features = [
   "compiler-builtins-mem",
-  "panic_immediate_abort",
   "default",
 ]
+panic-immediate-abort = true
 
 [profile.dev]
-panic = "abort"
+panic = "immediate-abort"
+
+[profile.release]
+panic = "immediate-abort"
 
 [build]
 rustflags = [

rust-toolchain.toml

@@ -1,5 +1,5 @@
 [toolchain]
-channel = "nightly-2025-08-18"
+channel = "nightly-2025-11-20"
 targets = ["riscv32im-unknown-none-elf"]
 # We need the sources for build-std.
 components = ["rust-src"]