This chapter describes the C compiler options in alphabetical order. See Appendix A, Compiler Options Grouped by Functionality for options grouped by functionality. For example, Table A-1 lists all the optimization and performance options.
Take note that the C compiler recognizes by default some of the constructs of the 1999 ISO/IEC C standard. Specifically, the supported features are detailed in Appendix D, Supported Features of C99. Use the -xc99=none command if you want to limit the compiler to the 1990 ISO/IEC C standard.
If you are porting a K&R (Kernighan and Ritchie) C program to ISO C, make special note of the section on compatibility flags, B.2.68 -X[c|a|t|s]. Using them makes the transition to ISO C easier. Also refer to the discussion on the transition in 5.4 Examples of Memory Reference Constraints.