C17 (C standard revision)

C17 is the informal name for ISO/IEC 9899:2018, a standard for the C programming language, prepared in 2017 and published in June 2018. It replaced C11 (standard ISO/IEC 9899:2011), and will be superseded by C23 (ISO/IEC 9899:2023) when it is published in 2024. Since it was under development in 2017, and officially published in 2018, C17 is sometimes referred to as C18.

Changes from C11
C17 fixes numerous minor defects in C11 without introducing new language features.

The  macro is increased to the value.

For a detailed list of changes from the previous standard, see Clarification Request Summary for C11.

Compiler support
List of compilers supporting C17:
 * GCC 8.1.0
 * LLVM Clang 7.0.0
 * IAR EWARM v8.40.1
 * Microsoft Visual C++ VS 2019 (16.8)
 * Pelles C 9.00