Compiler Version not Found After Downloading

Question

When I truffle compile, it says "Error: Could not find a compiler version matching ^0.8.11". I did some research and installed solc (npm install -g [email protected]), but it didn't fix the error.

In my smart contract I have pragma solidity ^0.8.11; declared at the top, and solcjs --version outputs 0.8.11+commit.d7f03943.Emscripten.clang. I also have the following in my project folder's truffle-config.js:

module.exports = {

  networks: {
    //All code in here is commented out by default
  },

  // Set default mocha options here, use special reporters etc.
  mocha: {
    // timeout: 100000
  },

  // Configure your compilers
  compilers: {
    solc: {
      version: "0.8.11",    // Fetch exact version from solc-bin (default: truffle's version)
      // docker: true,        // Use "0.5.1" you've installed locally with docker (default: false)
      // settings: {          // See the solidity docs for advice about optimization and evmVersion
      //  optimizer: {
      //    enabled: false,
      //    runs: 200
      //  },
      //  evmVersion: "byzantium"
      // }
    }
  },
}

This GitHub issue here determined that issue was a permissions error where Solidity couldn't read from the compilers folder, but I own the truffle folder & gave everybody read+write permissions in an attempt to allow Solidity to find the compiler inside:

15:21:38 [<user>@<server>1t2:1 /usr/local/lib/node_modules]
$ ls -al
drwxr-xr-x  3 vabzbt teusers 236 Feb 22 14:51 solc
drwxr-xr-x  6 vabzbt teusers 180 Feb 21 14:42 truffle

Why is Truffle still unable to find the version of solc that I installed? I tried removing the ^ or changing it to > in my pragma solidity statement & truffle-config info but neither of those worked. fwiw, this is on an enterprise machine that can't connect to the internet, and is mostly limited to internal mirrors of repos & such.

Answer 1

We have a solution!

I determined that this was a proxy error, but I don't know how to solve it. When truffle compile was run, it had issues connecting to the internet to get potential compiler versions.

As a workaround, You can download the relevant Solidity version at https://github.com/ethereum/solc-bin/tree/gh-pages/bin, and put it in ~/.config/truffle/compilers/node_modules. It does NOT work to download solc through npm and move it from /usr/local/lib/node_modules to the /.config/truffle/... folder.