A.2.4 Keywords
The following identifiers are reserved for the use as keywords, and may not be used otherwise:
- auto double int struct break else long switch case enum register typedef char extern return union const float short unsigned continue for signed void default goto sizeof volatile do if static while
Some implementations also reserve the words fortran and asm.
- The keywords const, signed, and volatile are new with the ANSI standard; enum and void are new since the first edition, but in common use; entry, formerly reserved but never used, is no longer reserved.