Solidity Compiler won't upgrade

Question

I updated to the latest version of Truffle using:

npm uninstall -g truffle

followed by:

npm install -g truffle

I verified this succeeded by doing:

truffle --version

and got this:

You can clearly see that I'm on version 5.0.3

I read that updating Truffle would pretty much also automatically update the Solidity compiler.

but when I do:

solc --version

I get this:

So its still on version 0.4.24

So I did again.
And again.
And its not working.

I've done it globally - and I've done it locally, meaning in my specific project's Directory.

Nothing works.

I tried doing it directly, by uninstalling Solidity - like this:

npm uninstall solc -g

-then reinstalling it using:

npm install solc -g

I've done pretty much everything I can think of, but its still telling me that I'm on version 0.4.24.

What's going on? What am I missing here?

========================================================

UPDATE:

I added the following to my truffle.js file:

compilers: {
    solc: {
        version: "0.5.0"  // ex:  "0.4.20". (Default: Truffle's installed solc)
    }
}

That's obviously supposed to force the use of that particular version of the compiler.

I recompiled and redeployed to ropsten - and that all worked.

So at this point, I'm assuming that the project is being compiled using v 0.5.0 of Solidity - but is it?

Here's my big question right now: how can I tell - like during run time, what compiler version is actually being used on my project at any given time? Cause at this point, I'm still getting errors in my DApp - the HTML & JS files that are querying the contract I deployed - that seem to do with the compiler+solidity versions - which was the reason I updated truffle to version 5 in the first place, to solve these issued. (But that's another matter. One thing at a time.)

===========================================================================

UPDATE#2

This shows everything:

-I'm installing solc v. 0.5.3 directly into my project's folder (I've already done the Global install several times.)

-I get 2 warnings - I don't know what they mean - but it says it installed 14 packages from 5 contributors, which sounds pretty good.

-but then when I do solc version, it tells me I'm on version 0.4.24

I've literally spent all day trying to resolve this.

Answer 1

On your project root directory, there's a file named "truffle-config.js"

Inside this file, you can find a solc config, and uncomment version line, and then put your prefer version. (ex: 0.5.7)

compilers: {
    solc: {
       version: "0.5.7",    // 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"
      // }
    }
  }

After this, just compile and truffle will download that version of solc automatically.

$ truffle compile 

Boom!