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12 Portable Make Programming

Writing portable makefiles is an art. Since a makefile’s commands are executed by the shell, you must consider the shell portability issues already mentioned. However, other issues are specific to make itself.

• $< in Ordinary Make Rules
• Failure in Make Rules
• Special Characters in Make Macro Names
• Backslash-Newline Before Empty Lines
• Backslash-Newline in Make Comments
• Long Lines in Makefiles
• make macro=value and Submakes
• The Make Macro MAKEFLAGS
• The Make Macro SHELL
• Parallel Make
• Comments in Make Rules
• Newlines in Make Rules
• Comments in Make Macros
• Trailing whitespace in Make Macros
• Command-line Macros and whitespace
• The obj/ Subdirectory and Make
• Exit Status of make -k
• VPATH and Make
• Single Suffix Rules and Separated Dependencies
• Timestamp Resolution and Make