C User's Guide

Chapter 1

Introduction to the C Compiler

This chapter provides information about the C compiler, including operating environments, standards conformance, organization of the compiler, and C-related programming tools.

Standards Conformance

The compiler conforms to the American National Standard for Programming Language - C, ANSI/ISO 9899-1990. It also conforms to ISO/IEC 9899:1990, Programming Languages - C. Finally, this compiler conforms to FIPS 160. Because the compiler also supports traditional K&R C (Kernighan and Ritchie, or pre-ANSI C), it can ease your migration to ANSI/ISO C.

Organization of the Compiler

The C compilation system consists of a compiler, an assembler, and a link editor. The cc command invokes each of these components automatically unless you use command-line options to specify otherwise.

"cc Compiler Options" on page 37 discusses all the options available with cc.

The following figure shows the organization of the C compilation system.

FIGURE 1-1   Organization of the C Compilation System

The following table summarizes the components of the compilation system.

TABLE 1-1   Components of the C Compilation System

Component	Description	Notes on Use
cpp	Preprocessor	-Xs
acomp	Compiler (preprocessor built in for non-Xs modes)
iropt	Code optimizer	(SPARC) -O, -xO [2-5], -fast
cg386	Intermediate language translator	(Intel) Always invoked
inline	Inline expansion of assembly language templates	.il file specified
mwinline	Automatic inline expansion of functions	(Intel) -xO4, -xinline
fbe	Assembler
cg	Code generator, inliner, assembler	(SPARC)
codegen	Code generator	(Intel)
ld	Linker
ild	Incremental linker	(SPARC) -g, -xildon

The C compiler optimizer removes redundancies, optimally allocates registers, schedules instructions, and reorganizes code. Select from multiple levels of optimization to obtain the best balance between application speed and use of memory.

C-Related Programming Tools

There are a number of tools available to aid in developing, maintaining, and improving your C programs. The two most closely tied to C, cscope and lint, are described in this book. In addition, a man page exists for each of these tools. Refer to the preface of this book for a list of all the associated man pages.

Sun WorkShop also provides tools for source browsing, debugging and performance analysis. See Related Documentation for more information.