D Common C Extensions Supported by DEC C

DEC C supports several common C (old-style C) extensions to ANSI- standard C. These extensions are recognized only when the common C compatibility option is used on the compiler command line. The common C extensions allow you to use the c89 compiler to compile code originally written for the portable C compiler (pcc).

The following sections describe the common C extensions available with the common C compatibility option. Extensions to the ANSI- standard C language are divided into two categories:

• Extensions compatible with ANSI C programs that produce diagnostic messages when compiled without the common C compatibility option

• Extensions incompatible with ANSI C programs, which could produce different compiler behavior when used without the common C compatibility option