3-1 Size of Integer Type The SuperH development environment is the integrated development environment which is called as HEW. HEW is included in the compiler package product. And it includes the cross tool chains like C/C++ compiler, assembler, the optimal linkage editor and. The C/C++ compiler language is based on ANSI/ISO standards. Standard optimizations feature including the deletion of common expression from general source codes and the register allocation are provided at the compiler. In additional optimizations which use special function on the each SH CPU are implemented like the pipeline operations and special. It also supports extended functions that are needed for the development of embedded programs, such as declaration of interrupt functions and executing of CPU-specific instructions. These features are not specified by ANSI language specifications. Some parts of C language specifications like a size of short type are not specified clear since it depends on the microcomputer architecture. It is decided by the compiler implementer. Therefore it may not be possible to ensure compatibility for these parts since they are implemented differently depending on the compiler. They are the size of variables which does not include “char” type, memory assignment for Structure and Union, 2-byte character, etc. We introduce SH Compiler’s language specification.Type of variables and function are here. Type of “char” variable is signed char.