# Error on contract compilation and optimization **URL:** \ **Category:** Developer Help\ **Created:** [February 27, 2022, 5:30pm UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522 "2022-02-27T17:30:31Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![arefin97](https://avatars.discourse-cdn.com/v4/letter/a/7ba0ec/32.png) [@arefin97](https://forum.scrt.network/u/arefin97)\ **Post date:** [February 27, 2022, 5:30pm UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522/1 "2022-02-27T17:30:31Z")
when I run the following command to optimize my smart contract, it shows me the error given below. But my rustc version is updated and it is 1.58.1 $docker run --rm -v “$(pwd)”:/contract --mount type=volume,source="$(basename “$(pwd)”)\_cache",target=/code/target --mount type=volume,source=registry\_cache,target=/usr/local/cargo/registry enigmampc/secret-contract-optimizer error: package `uint v0.9.3` cannot be built because it requires rustc 1.56.1 or newer, while the currently active rustc version is 1.56.0 //Command to check rustc version: $rustup --version rustup 1.24.3 (ce5817a94 2021-05-31) info: This is the version for the rustup toolchain manager, not the rustc compiler. info: The currently active `rustc` version is `rustc 1.58.1 (db9d1b20b 2022-01-20)` ---
**Author:** ![DDT](https://yyz1.discourse-cdn.com/flex035/user_avatar/forum.scrt.network/ddt/32/3086_2.png) [@DDT](https://forum.scrt.network/u/DDT)\ **Post date:** [February 27, 2022, 6:31pm UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522/2 "2022-02-27T18:31:38Z")
I had this issue recently too, ie: not compiling and saying I have an older version of rustc than I actually did. I installed clang and it worked, at least for me. ---
**Author:** ![arefin97](https://avatars.discourse-cdn.com/v4/letter/a/7ba0ec/32.png) [@arefin97](https://forum.scrt.network/u/arefin97)\ **Post date:** [February 27, 2022, 6:48pm UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522/3 "2022-02-27T18:48:00Z")
yeah, i faced this issue as well when tried to compile. After installing clang compilation worked fine. but now the problem is in optimization which it will generate ‘contract.wasm’ file. ---
**Author:** ![DDT](https://yyz1.discourse-cdn.com/flex035/user_avatar/forum.scrt.network/ddt/32/3086_2.png) [@DDT](https://forum.scrt.network/u/DDT)\ **Post date:** [March 4, 2022, 6:21pm UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522/4 "2022-03-04T18:21:52Z")
Hey if you are still facing the issue, I think the reason is because you are using the v1.0.5 optimizer (docker image), which I THINK is using Rust 1.56. Try using optimizer v1.0.6? ---
**Author:** ![assafmo](https://yyz1.discourse-cdn.com/flex035/user_avatar/forum.scrt.network/assafmo/32/440_2.png) [@assafmo](https://forum.scrt.network/u/assafmo)\ **Post date:** [March 6, 2022, 9:06am UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522/5 "2022-03-06T09:06:36Z")
Yes, please use v1.0.6 of the optimizer, I’ve updated it to use rust 1.59. ---
**Author:** ![arefin97](https://avatars.discourse-cdn.com/v4/letter/a/7ba0ec/32.png) [@arefin97](https://forum.scrt.network/u/arefin97)\ **Post date:** [March 6, 2022, 4:22pm UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522/6 "2022-03-06T16:22:48Z")
Yeah, thanks everybody. I have sorted out this by changing in script though. But I appreciate your helps very much. ---
**Author:** ![jacob\_puzzle](https://avatars.discourse-cdn.com/v4/letter/j/a183cd/32.png) [@jacob\_puzzle](https://forum.scrt.network/u/jacob_puzzle)\ **Post date:** [September 23, 2022, 12:12am UTC](https://forum.scrt.network/t/error-on-contract-compilation-and-optimization/5522/7 "2022-09-23T00:12:43Z")
I’m running into the same error using the latest version of the contract optimizer. I’ve got rustc 1.64.0 as my active version, running on ubuntu 20.04.