toolchain pinned to 2025-08-18

Author: kunxian-xia

.github/workflows/lint.yml

@@ -25,7 +25,7 @@ jobs:
           components: rustfmt, clippy, rust-src
           targets: riscv32im-unknown-none-elf
           # TODO: figure out way to keep this in sync with rust-toolchain.toml automatically
-          toolchain: nightly-2025-08-19
+          toolchain: nightly-2025-08-18
       - name: Give Github Action access to ceno-gpu
         uses: webfactory/ssh-agent@v0.9.0
         with:

.github/workflows/pr.yml

@@ -29,7 +29,7 @@ jobs:
       - name: "Setup nightly toolchain"
         uses: "actions-rs/toolchain@v1"
         with:
-          toolchain: nightly-2025-08-19
+          toolchain: nightly-2025-08-18
           components: rustfmt, clippy
           override: true
 
@@ -93,7 +93,7 @@ jobs:
         with:
           components: rust-src
           targets: riscv32im-unknown-none-elf
-          # TODO: figure out why cargo-ceno does not work with nightly-2025-08-19
+          # TODO: figure out why cargo-ceno does not work with nightly-2025-08-18
           toolchain: nightly-2025-08-18
 
       - name: "Build cargo-ceno toolchain"