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4.9 Special Built-in Target Names

Certain names have special meanings if they appear as targets.

.PHONY
The prerequisites of the special target .PHONY are considered to be phony targets. When it is time to consider such a target, make will run its recipe unconditionally, regardless of whether a file with that name exists or what its last-modification time is. See Phony Targets.


.SUFFIXES
The prerequisites of the special target .SUFFIXES are the list of suffixes to be used in checking for suffix rules. See Old-Fashioned Suffix Rules.


.DEFAULT
The recipe specified for .DEFAULT is used for any target for which no rules are found (either explicit rules or implicit rules). See Last Resort. If a .DEFAULT recipe is specified, every file mentioned as a prerequisite, but not as a target in a rule, will have that recipe executed on its behalf. See Implicit Rule Search Algorithm.


.PRECIOUS
The targets which .PRECIOUS depends on are given the following special treatment: if make is killed or interrupted during the execution of their recipes, the target is not deleted. See Interrupting or Killing make. Also, if the target is an intermediate file, it will not be deleted after it is no longer needed, as is normally done. See Chains of Implicit Rules. In this latter respect it overlaps with the .SECONDARY special target.

You can also list the target pattern of an implicit rule (such as ‘%.o’) as a prerequisite file of the special target .PRECIOUS to preserve intermediate files created by rules whose target patterns match that file's name.


.INTERMEDIATE
The targets which .INTERMEDIATE depends on are treated as intermediate files. See Chains of Implicit Rules. .INTERMEDIATE with no prerequisites has no effect.


.SECONDARY
The targets which .SECONDARY depends on are treated as intermediate files, except that they are never automatically deleted. See Chains of Implicit Rules.

.SECONDARY with no prerequisites causes all targets to be treated as secondary (i.e., no target is removed because it is considered intermediate).


.SECONDEXPANSION
If .SECONDEXPANSION is mentioned as a target anywhere in the makefile, then all prerequisite lists defined after it appears will be expanded a second time after all makefiles have been read in. See Secondary Expansion.


.DELETE_ON_ERROR
If .DELETE_ON_ERROR is mentioned as a target anywhere in the makefile, then make will delete the target of a rule if it has changed and its recipe exits with a nonzero exit status, just as it does when it receives a signal. See Errors in Recipes.


.IGNORE
If you specify prerequisites for .IGNORE, then make will ignore errors in execution of the recipe for those particular files. The recipe for .IGNORE (if any) is ignored.

If mentioned as a target with no prerequisites, .IGNORE says to ignore errors in execution of recipes for all files. This usage of ‘.IGNORE’ is supported only for historical compatibility. Since this affects every recipe in the makefile, it is not very useful; we recommend you use the more selective ways to ignore errors in specific recipes. See Errors in Recipes.


.LOW_RESOLUTION_TIME
If you specify prerequisites for .LOW_RESOLUTION_TIME, make assumes that these files are created by commands that generate low resolution time stamps. The recipe for the .LOW_RESOLUTION_TIME target are ignored.

The high resolution file time stamps of many modern file systems lessen the chance of make incorrectly concluding that a file is up to date. Unfortunately, some hosts do not provide a way to set a high resolution file time stamp, so commands like ‘cp -p’ that explicitly set a file's time stamp must discard its sub-second part. If a file is created by such a command, you should list it as a prerequisite of .LOW_RESOLUTION_TIME so that make does not mistakenly conclude that the file is out of date. For example:

          .LOW_RESOLUTION_TIME: dst
          dst: src
                  cp -p src dst

Since ‘cp -p’ discards the sub-second part of src's time stamp, dst is typically slightly older than src even when it is up to date. The .LOW_RESOLUTION_TIME line causes make to consider dst to be up to date if its time stamp is at the start of the same second that src's time stamp is in.

Due to a limitation of the archive format, archive member time stamps are always low resolution. You need not list archive members as prerequisites of .LOW_RESOLUTION_TIME, as make does this automatically.


.SILENT
If you specify prerequisites for .SILENT, then make will not print the recipe used to remake those particular files before executing them. The recipe for .SILENT is ignored.

If mentioned as a target with no prerequisites, .SILENT says not to print any recipes before executing them. This usage of ‘.SILENT’ is supported only for historical compatibility. We recommend you use the more selective ways to silence specific recipes. See Recipe Echoing. If you want to silence all recipes for a particular run of make, use the ‘-s’ or ‘--silent option (see Options Summary).


.EXPORT_ALL_VARIABLES
Simply by being mentioned as a target, this tells make to export all variables to child processes by default. See Communicating Variables to a Sub-make.


.NOTPARALLEL
If .NOTPARALLEL is mentioned as a target, then this invocation of make will be run serially, even if the ‘-j’ option is given. Any recursively invoked make command will still run recipes in parallel (unless its makefile also contains this target). Any prerequisites on this target are ignored.


.ONESHELL
If .ONESHELL is mentioned as a target, then when a target is built all lines of the recipe will be given to a single invocation of the shell rather than each line being invoked separately (see Recipe Execution).


.POSIX
If .POSIX is mentioned as a target, then the makefile will be parsed and run in POSIX-conforming mode. This does not mean that only POSIX-conforming makefiles will be accepted: all advanced GNU make features are still available. Rather, this target causes make to behave as required by POSIX in those areas where make's default behavior differs.

In particular, if this target is mentioned then recipes will be invoked as if the shell had been passed the -e flag: the first failing command in a recipe will cause the recipe to fail immediately.

Any defined implicit rule suffix also counts as a special target if it appears as a target, and so does the concatenation of two suffixes, such as ‘.c.o’. These targets are suffix rules, an obsolete way of defining implicit rules (but a way still widely used). In principle, any target name could be special in this way if you break it in two and add both pieces to the suffix list. In practice, suffixes normally begin with ‘.’, so these special target names also begin with ‘.’. See Old-Fashioned Suffix Rules.