---
title: CLanguageStandard
framework: packagedescription
role: symbol
role_heading: Enumeration
path: packagedescription/clanguagestandard
---

# CLanguageStandard

The supported C language standard you use to compile C sources in the package.

## Declaration

```swift
enum CLanguageStandard
```

## Topics

### Enumeration Cases

- [CLanguageStandard.c11](packagedescription/clanguagestandard/c11.md)
- [CLanguageStandard.c17](packagedescription/clanguagestandard/c17.md)
- [CLanguageStandard.c18](packagedescription/clanguagestandard/c18.md)
- [CLanguageStandard.c2x](packagedescription/clanguagestandard/c2x.md)
- [CLanguageStandard.c89](packagedescription/clanguagestandard/c89.md)
- [CLanguageStandard.c90](packagedescription/clanguagestandard/c90.md)
- [CLanguageStandard.c99](packagedescription/clanguagestandard/c99.md)
- [CLanguageStandard.gnu11](packagedescription/clanguagestandard/gnu11.md)
- [CLanguageStandard.gnu17](packagedescription/clanguagestandard/gnu17.md)
- [CLanguageStandard.gnu18](packagedescription/clanguagestandard/gnu18.md)
- [CLanguageStandard.gnu2x](packagedescription/clanguagestandard/gnu2x.md)
- [CLanguageStandard.gnu89](packagedescription/clanguagestandard/gnu89.md)
- [CLanguageStandard.gnu90](packagedescription/clanguagestandard/gnu90.md)
- [CLanguageStandard.gnu99](packagedescription/clanguagestandard/gnu99.md)
- [CLanguageStandard.iso9899_1990](packagedescription/clanguagestandard/iso9899_1990.md)
- [CLanguageStandard.iso9899_199409](packagedescription/clanguagestandard/iso9899_199409.md)
- [CLanguageStandard.iso9899_1999](packagedescription/clanguagestandard/iso9899_1999.md)
- [CLanguageStandard.iso9899_2011](packagedescription/clanguagestandard/iso9899_2011.md)
- [CLanguageStandard.iso9899_2017](packagedescription/clanguagestandard/iso9899_2017.md)
- [CLanguageStandard.iso9899_2018](packagedescription/clanguagestandard/iso9899_2018.md)

## Relationships

### Conforms To

- [Copyable](swift/copyable.md)
- [Equatable](swift/equatable.md)
- [Escapable](swift/escapable.md)
- [Hashable](swift/hashable.md)
- [RawRepresentable](swift/rawrepresentable.md)

## See Also

### Declaring Supported Languages

- [SwiftLanguageMode](packagedescription/swiftlanguagemode.md)
- [CXXLanguageStandard](packagedescription/cxxlanguagestandard.md)
- [swiftLanguageModes](packagedescription/package/swiftlanguagemodes.md)
- [cLanguageStandard](packagedescription/package/clanguagestandard.md)
- [cxxLanguageStandard](packagedescription/package/cxxlanguagestandard.md)
- [SwiftVersion](packagedescription/swiftversion.md)
- [swiftLanguageVersions](packagedescription/package/swiftlanguageversions.md)