Home/ Questions/Q 492177
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-13T02:05:09+00:00

I usually write C code in C89, now some features of C99 (like intxx_t

  • 0

I usually write C code in C89, now some features of C99 (like intxx_t or __VA_ARGS__ or snprintf) are very useful, and can be even vital.

Before I more my requirements from C89 to C99 I wanted to know which of C99 features were widely supported and which ones were not widely supported or even considered harmful.

I know we could just check our target compiler support, but this would narrow our support a lot, and as this is for open source software, I’d prefer having a wider support.

For example, we use Solaris (suncc) compiler and gcc, but there might be other compiler we would move out of the way while we could keep compatibility with very little efforts.

For example, I never worked on Windows nor I know anything about Windows compilers, but it would be good to keep Windows compatibility.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    A number of C99 features are optional, so their lack isn’t technically non-conforming. I won’t distinguish below.

    • Hmm, win doesn’t have <stdint.h>, although there is an open-source version of stdint.h for Microsoft. Even when the file is implemented, many of the individual types are missing.

    • Complex and imaginary support is often missing or broken.

    • Extended identifiers and wide characters can be problem points.

    See this list of C99 feature issues in gcc.

    • 0