3.6.7 Options for Controlling the Preprocessor

The options tabulated below control the preprocessor and are discussed in the sections that follow.

Table 3-17. Preprocessor Options
Option

(links to explanatory section)

 Controls
-C Preserve comments
-dletters Preserve macro definitions
-Dmacro

-Dmacro=defn

 Define a macro
-fno-show-column Omit column numbers in diagnostics
-H Print header file name
-imacros file Include file macro definitions only
-include file Include file
-M Generate make rule
-MD Write dependency information to file
-MF file Specify dependency file
-MG Ignore missing header files
-MM Generate make rule for quoted headers
-MMD Generate make rule for user headers
-MP Add phony target for dependency
-MQ Change rule target with quotes
-MT target Change rule target
-P Don’t generate #line directives
-trigraphs Support trigraphs
-Umacro Undefine macros
-undef Do not predefine nonstandard macros