Are there any features in C language that are not in C++?

Yes. There are a number of features in C language that are not in C++, most of which are the features which were introduced in the C99 standard. Below is a list of features that are not available in C++, but available in C language:

• Implicit casting of void pointers
• long long type
• Calling main function recursively.
• restrict keyword
• Variadic macros
• Variable length arrays
• Flexible array members
• Designated initializers
• Compound literals

References

Tech Talk About C99 Comeau C99 FAQ∞
Incompatibilities Between ISO C and ISO C++∞