Substrate Node Template Build Error, syn::group private

Question

while building substrate node template versions: polkadot-v0.9.19, polkadot-v0.9.27 get the below error rustup version

nightly-2022-02-15-x86_64-unknown-linux-gnu (default)
rustc 1.60.0-nightly (c5c610aad 2022-02-14)

Answer 1

Just simply do this (you don't have to modify the lock file manually):

cargo update -p syn --precise 1.0.96

---

If you have the plan to update your Substrate version.

Update the Substrate to this commit, which could fix this problem permanently.

Answer 2

Downgrade your current syn version 1.0.99 into 1.0.96 in my case

Step:

• Go to Cargo.lock
• Search name = "syn" in Cargo.lock
• Delete checksum line of syn
• Replace 1.0.99 by 1.0.96
• cargo build --release again