## 3.1.3 ISO C99

Use —std-c99 to compile in this mode.

In addition to what is mentioned in the section above, the following features of this standard are not supported by SDCC:

- Compound literals.
- Objects of variably-modified types.
- ptrdiff_t has 16 bits, while the standard requires at least 17 bits.

Some features of this standard are not supported in some ports:

- pic14, pic16: there is no support for data types long long, unsigned long long, int_fast64_t, int_least64_t, int64_t, uint_fast64_t, uint_least64_t, uint64_t.