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(make.info.gz) Special Targets

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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 commands unconditionally, regardless of
      whether a file with that name exists or what its last-modification
      time is.   Phony Targets Phony Targets.
 
 `.SUFFIXES'
      The prerequisites of the special target `.SUFFIXES' are the list
      of suffixes to be used in checking for suffix rules.  
      Old-Fashioned Suffix Rules Suffix Rules.
 
 `.DEFAULT'
      The commands specified for `.DEFAULT' are used for any target for
      which no rules are found (either explicit rules or implicit rules).
       Last Resort.  If `.DEFAULT' commands are specified, every
      file mentioned as a prerequisite, but not as a target in a rule,
      will have these commands executed on its behalf.   Implicit
      Rule Search Algorithm Implicit Rule Search.
 
 `.PRECIOUS'
      The targets which `.PRECIOUS' depends on are given the following
      special treatment: if `make' is killed or interrupted during the
      execution of their commands, the target is not deleted.  
      Interrupting or Killing `make' Interrupts.  Also, if the target
      is an intermediate file, it will not be deleted after it is no
      longer needed, as is normally done.   Chains of Implicit
      Rules Chained 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.   Chains of Implicit Rules Chained 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.   Chains of Implicit Rules Chained 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.   Secondary Expansion Secondary Expansion.
 
      The prerequisites of the special target `.SUFFIXES' are the list
      of suffixes to be used in checking for suffix rules.  
      Old-Fashioned Suffix Rules Suffix Rules.
 
 `.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 commands exit with a nonzero exit status, just as
      it does when it receives a signal.   Errors in Commands
      Errors.
 
 `.IGNORE'
      If you specify prerequisites for `.IGNORE', then `make' will
      ignore errors in execution of the commands run for those particular
      files.  The commands for `.IGNORE' are not meaningful.
 
      If mentioned as a target with no prerequisites, `.IGNORE' says to
      ignore errors in execution of commands for all files.  This usage
      of `.IGNORE' is supported only for historical compatibility.  Since
      this affects every command in the makefile, it is not very useful;
      we recommend you use the more selective ways to ignore errors in
      specific commands.   Errors in Commands Errors.
 
 `.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 commands for `.LOW_RESOLUTION_TIME'
      are not meaningful.
 
      The high resolution file time stamps of many modern hosts lessen
      the chance of `make' incorrectly concluding that a file is up to
      date.  Unfortunately, these hosts provide no 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 subsecond
      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 subsecond 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 commands to remake those particular files before
      executing them.  The commands for `.SILENT' are not meaningful.
 
      If mentioned as a target with no prerequisites, `.SILENT' says not
      to print any commands before executing them.  This usage of
      `.SILENT' is supported only for historical compatibility.  We
      recommend you use the more selective ways to silence specific
      commands.   Command Echoing Echoing.  If you want to silence
      all commands for a particular run of `make', use the `-s' or
      `--silent' option ( Options Summary).
 
 `.EXPORT_ALL_VARIABLES'
      Simply by being mentioned as a target, this tells `make' to export
      all variables to child processes by default.   Communicating
      Variables to a Sub-`make' Variables/Recursion.
 
 `.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 be run in
      parallel (unless its makefile contains this target).  Any
      prerequisites on this target are ignored.
 
    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 `.'.
  Old-Fashioned Suffix Rules Suffix Rules.
 
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