Copyright 1989 AT&T
Portions Copyright (c) 1992, X/Open Company Limited All Rights Reserved
Copyright (c) 2008, Sun Microsystems, Inc. All Rights Reserved
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/usr/bin/make [-d] [-dd] [-D] [-DD] [-e] [-i] [-j \FImaxjobs] [-k] [-m {serial | parallel}] [-n] [-p] [-P] [-q] [-r] [-s] [-S] [-t] [-V] [-f makefile]... [-K statefile]... [target]... [macro = value...]
/usr/bin/dmake [-d] [-dd] [-D] [-DD] [-e] [-i] [-j \FImaxjobs] [-k] [-m {serial | parallel}] [-n] [-p] [-P] [-q] [-r] [-s] [-S] [-t] [-V] [-f makefile]... [-K statefile]... [target]... [macro = value...]
/usr/xpg4/bin/make [-d] [-dd] [-D] [-DD] [-e] [-i] [-j \FImaxjobs] [-k] [-m {serial | parallel}] [-n] [-p] [-P] [-q] [-r] [-s] [-S] [-t] [-V] [-f makefile]... [target]... [macro = value...]
The make utility executes a list of shell commands associated with each target, typically to create or update a file of the same name. makefile contains entries that describe how to bring a target up to date with respect to those on which it depends, which are called dependencies. Since each dependency is a target, it can have dependencies of its own. Targets, dependencies, and sub-dependencies comprise a tree structure that make traces when deciding whether or not to rebuild a target.
The make utility recursively checks each target against its dependencies, beginning with the first target entry in makefile if no target argument is supplied on the command line. If, after processing all of its dependencies, a target file is found either to be missing, or to be older than any of its dependencies, make rebuilds it. Optionally with this version of make, a target can be treated as out-of-date when the commands used to generate it have changed since the last time the target was built.
To build a given target, make executes the list of commands, called a rule. This rule can be listed explicitly in the target's makefile entry, or it can be supplied implicitly by make.
If no target is specified on the command line, make uses the first target defined in makefile.
If a target has no makefile entry, or if its entry has no rule, make attempts to derive a rule by each of the following methods, in turn, until a suitable rule is found. Each method is described under Usage below.
Pattern matching rules.
Implicit rules, read in from a user-supplied makefile.
Standard implicit rules (also known as suffix rules), typically read in from the file /usr/share/lib/make/make.rules.
SCCS retrieval. make retrieves the most recent version from the SCCS history file (if any). See the description of the .SCCS_GET: special-function target for details.
The rule from the .DEFAULT: target entry, if there is such an entry in the makefile.
If there is no makefile entry for a target, if no rule can be derived for building it, and if no file by that name is present, make issues an error message and halts.
The following options are supported: -d
Displays the reasons why make chooses to rebuild a target. make displays any and all dependencies that are newer. In addition, make displays options read in from the MAKEFLAGS environment variable.
Displays the dependency check and processing in vast detail.
Displays the text of the makefiles read in.
Displays the text of the makefiles, make.rules file, the state file, and all hidden-dependency reports.
Environment variables override assignments within makefiles.
Uses the description file makefile. A - as the makefile argument denotes the standard input. The contents of makefile, when present, override the standard set of implicit rules and predefined macros. When more than one -f makefile argument pair appears, make uses the concatenation of those files, in order of appearance. When no makefile is specified, /usr/bin/make tries the following in sequence, except when in POSIX mode (see .POSIX in Usage):
If there is a file named makefile in the working directory, make uses that file. If, however, there is an SCCS history file (SCCS/s.makefile) which is newer, make attempts to retrieve and use the most recent version.
In the absence of the above file(s), if a file named Makefile is present in the working directory, make attempts to use it. If there is an SCCS history file (SCCS/s.Makefile) that is newer, make attempts to retrieve and use the most recent version.
./makefile, ./Makefile
s.makefile, SCCS/s.makefile
s.Makefile, SCCS/s.Makefile
Ignores error codes returned by commands. Equivalent to the special-function target .IGNORE:.
Specify the maximum number of jobs that each instance of make will invoke.
When a nonzero error status is returned by a rule, or when make cannot find a rule, abandons work on the current target, but continues with other dependency branches that do not depend on it.
Uses the state file statefile. A - as the statefile argument denotes the standard input. The contents of statefile, when present, override the standard set of implicit rules and predefined macros. When more than one -K statefile argument pair appears, make uses the concatenation of those files, in order of appearance. (See also .KEEP_STATE and .KEEP_STATE_FILE in the Special-Function Targets section).
Specify whether make should execute jobs serially or in parallel. The default for make is to run serially unless -j is specified. The default is for dmake is to run in parallel.
No execution mode. Prints commands, but does not execute them. Even lines beginning with an @ are printed. However, if a command line contains a reference to the $(MAKE) macro, that line is always executed (see the discussion of MAKEFLAGS in Reading Makefiles and the Environment). When in POSIX mode, lines beginning with a "+" are executed.
Prints out the complete set of macro definitions and target descriptions.
Merely reports dependencies, rather than building them.
Question mode. make returns a zero or nonzero status code depending on whether or not the target file is up to date. When in POSIX mode, lines beginning with a "+" are executed.
Does not read in the default makefile /usr/share/lib/make/make.rules.
Silent mode. Does not print command lines before executing them. Equivalent to the special-function target .SILENT:.
Undoes the effect of the -k option. Stops processing when a non-zero exit status is returned by a command.
Touches the target files (bringing them up to date) rather than performing their rules. Warning: This can be dangerous when files are maintained by more than one person. When the .KEEP_STATE: target appears in the makefile, this option updates the state file just as if the rules had been performed. When in POSIX mode, lines beginning with a "+" are executed.
Puts make into SysV mode. Refer to sysV-make(1) for respective details.
The following operands are supported: target
Target names, as defined in Usage.
Macro definition. This definition overrides any regular definition for the specified macro within the makefile itself, or in the environment. However, this definition can still be overridden by conditional macro assignments.
The usage of make is described below:
When make first starts, it reads the MAKEFLAGS environment variable to obtain any of the following options specified present in its value: -d, -D, -e, -i, -k, -n, -p, -q, -r, -s, -S, or -t. Due to the implementation of POSIX.2 (see POSIX.2(5), the MAKEFLAGS values contains a leading - character. The make utility then reads the command line for additional options, which also take effect.
Next, make reads in a default makefile that typically contains predefined macro definitions, target entries for implicit rules, and additional rules, such as the rule for retrieving SCCS files. If present, make uses the file make.rules in the current directory; otherwise it reads the file /usr/share/lib/make/make.rules, which contains the standard definitions and rules. Use the directive:
include /usr/share/lib/make/make.rules
in your local make.rules file to include them.
Next, make imports variables from the environment (unless the -e option is in effect), and treats them as defined macros. Because make uses the most recent definition it encounters, a macro definition in the makefile normally overrides an environment variable of the same name. When -e is in effect, however, environment variables are read in after all makefiles have been read. In that case, the environment variables take precedence over definitions in the makefile.
Next, make reads any makefiles you specify with -f, or one of makefile or Makefile as described above and then the state file, in the local directory if it exists. If the makefile contains a .KEEP_STATE_FILE target, then it reads the state file that follows the target. Refer to special target .KEEP_STATE_FILE for details.
Next (after reading the environment if -e is in effect), make reads in any macro definitions supplied as command line arguments. These override macro definitions in the makefile and the environment both, but only for the make command itself.
make exports environment variables, using the most recently defined value. Macro definitions supplied on the command line are not normally exported, unless the macro is also an environment variable.
make does not export macros defined in the makefile. If an environment variable is set, and a macro with the same name is defined on the command line, make exports its value as defined on the command line. Unless -e is in effect, macro definitions within the makefile take precedence over those imported from the environment.
The macros MAKEFLAGS, MAKE, SHELL, HOST_ARCH, HOST_MACH, and TARGET_MACH are special cases. See Special-Purpose Macros below for details.
A target entry has the following format:
target [:|::] [dependency] ... [; command] ... [command] ...
The first line contains the name of a target, or a space-separated list of target names, terminated with a colon or double colon. If a list of targets is given, this is equivalent to having a separate entry of the same form for each target. The colon(s) can be followed by a dependency, or a dependency list. make checks this list before building the target. The dependency list can be terminated with a semicolon (;), which in turn can be followed by a single Bourne shell command. Subsequent lines in the target entry begin with a TAB and contain Bourne shell commands. These commands comprise the rule for building the target.
Shell commands can be continued across input lines by escaping the NEWLINE with a backslash (\e). The continuing line must also start with a TAB.
To rebuild a target, make expands macros, strips off initial TAB characters and either executes the command directly (if it contains no shell metacharacters), or passes each command line to a Bourne shell for execution.
The first non-empty line that does not begin with a TAB or # begins another target or macro definition.
Special characters are defined below.
Start a comment. The comment ends at the next NEWLINE. If the # follows the TAB in a command line, that line is passed to the shell (which also treats # as the start of a comment).
If the word include appears as the first seven letters of a line and is followed by a SPACE or TAB, the string that follows is taken as a filename to interpolate at that line. include files can be nested to a depth of no more than 38 nested makefiles . If filename is a macro reference, it is expanded.
Target list terminator. Words following the colon are added to the dependency list for the target or targets. If a target is named in more than one colon-terminated target entry, the dependencies for all its entries are added to form that target's complete dependency list.
Target terminator for alternate dependencies. When used in place of a : the double-colon allows a target to be checked and updated with respect to alternate dependency lists. When the target is out-of-date with respect to dependencies listed in the first alternate, it is built according to the rule for that entry. When out-of-date with respect to dependencies in another alternate, it is built according the rule in that other entry. Implicit rules do not apply to double-colon targets; you must supply a rule for each entry. If no dependencies are specified, the rule is always performed.
Target group. The rule in the target entry builds all the indicated targets as a group. It is normally performed only once per make run, but is checked for command dependencies every time a target in the group is encountered in the dependency scan.
Pattern matching wild card metacharacter. Like the * shell wild card, % matches any string of zero or more characters in a target name or dependency, in the target portion of a conditional macro definition, or within a pattern replacement macro reference. Notice that only one % can appear in a target, dependency-name, or pattern-replacement macro reference.
make ignores the leading ./ characters from targets with names given as pathnames relative to "dot," the working directory.
Macro definition. The word to the left of this character is the macro name; words to the right comprise its value. Leading and trailing white space characters are stripped from the value. A word break following the = is implied.
Macro reference. The following character, or the parenthesized or bracketed string, is interpreted as a macro reference: make expands the reference (including the $) by replacing it with the macro's value.
{ }
Macro-reference name delimiters. A parenthesized or bracketed word appended to a $ is taken as the name of the macro being referred to. Without the delimiters, make recognizes only the first character as the macro name.
A reference to the dollar-sign macro, the value of which is the character $. Used to pass variable expressions beginning with $ to the shell, to refer to environment variables which are expanded by the shell, or to delay processing of dynamic macros within the dependency list of a target, until that target is actually processed.
Escaped dollar-sign character. Interpreted as a literal dollar sign within a rule.
When used in place of =, appends a string to a macro definition (must be surrounded by white space, unlike =).
Conditional macro assignment. When preceded by a list of targets with explicit target entries, the macro definition that follows takes effect when processing only those targets, and their dependencies.
Define the value of a macro to be the output of a command (see Command Substitutions below).
In a macro reference, execute the command stored in the macro, and replace the reference with the output of that command (see Command Substitutions below).
make always executes the commands preceded by a "+", even when -n is specified.
make ignores any nonzero error code returned by a command line for which the first non-TAB character is a -. This character is not passed to the shell as part of the command line. make normally terminates when a command returns nonzero status, unless the -i or -k options, or the .IGNORE: special-function target is in effect.
If the first non-TAB character is a @, make does not print the command line before executing it. This character is not passed to the shell.
Escape command-dependency checking. Command lines starting with this character are not subject to command dependency checking.
Force command-dependency checking. Command-dependency checking is applied to command lines for which it would otherwise be suppressed. This checking is normally suppressed for lines that contain references to the ? dynamic macro (for example, $?). When any combination of +, -, @, ?, or ! appear as the first characters after the TAB, all that are present apply. None are passed to the shell.
When incorporated in a makefile, the following target names perform special-functions: .DEFAULT:
If it has an entry in the makefile, the rule for this target is used to process a target when there is no other entry for it, no rule for building it, and no SCCS history file from which to retrieve a current version. make ignores any dependencies for this target.
If defined in the makefile, make processes this target and its dependencies after all other targets are built. This target is also performed when make halts with an error, unless the .FAILED target is defined.
This target, along with its dependencies, is performed instead of .DONE when defined in the makefile and make halts with an error.
This target contains the rule for retrieving the current version of an SCCS file from its history file in the current working directory. make uses this rule when it is running in POSIX mode.
Ignore errors. When this target appears in the makefile, make ignores non-zero error codes returned from commands. When used in POSIX mode, .IGNORE could be followed by target names only, for which the errors is ignored.
If defined in the makefile, this target and its dependencies are built before any other targets are processed.
If this target is in effect, make updates the state file, .make.state, in the current directory. This target also activates command dependencies, and hidden dependency checks. If either the .KEEP_STATE: target appears in the makefile, or the environment variable KEEP_STATE is set (setenv KEEP_STATE), make rebuilds everything in order to collect dependency information, even if all the targets were up to date due to previous make runs. See also the Environment Variables section. This target has no effect if used in POSIX mode.
This target has no effect if used in POSIX mode. This target implies .KEEP_STATE. If the target is followed by a filename, make uses it as the state file. If the target is followed by a directory name, make looks for a .make.state file in that directory. If the target is not followed by any name, make looks for .make.state file in the current working directory.
A target-entry of the form:
.MAKE_VERSION: VERSION-number
enables version checking. If the version of make differs from the version
indicated by a string like VERSION-1.0, make issues a warning
message.
Dependencies of this target will be executed serially.
Dependencies of this target will be executed in parallel.
This target enables POSIX mode.
List of files not to delete. make does not remove any of the files listed as dependencies for this target when interrupted. make normally removes the current target when it receives an interrupt. When used in POSIX mode, if the target is not followed by a list of files, all the file are assumed precious.
This target contains the rule for retrieving the current version of an SCCS file from its history file. To suppress automatic retrieval, add an entry for this target with an empty rule to your makefile.
This target contains the rule for retrieving the current version of an SCCS file from its history file. make uses this rule when it is running in POSIX mode.
Run silently. When this target appears in the makefile, make does not echo commands before executing them. When used in POSIX mode, it could be followed by target names, and only those are executed silently.
The suffixes list for selecting implicit rules (see The Suffixes List).
In a dependency list, wait until any dependency preceding this has completed before moving on to any dependency following it.
In this version of make, you can clear the definition of the following special targets by supplying entries for them with no dependencies and no rule:
.DEFAULT, .SCCS_GET, and .SUFFIXES
When the .KEEP_STATE: target is effective, make checks the command for building a target against the state file. If the command has changed since the last make run, make rebuilds the target.
When the .KEEP_STATE: target is effective, make reads reports from cpp(1) and other compilation processors for any "hidden" files, such as #include files. If the target is out of date with respect to any of these files, make rebuilds it.
Entries of the form
macro=value
define macros. macro is the name of the macro, and value, which consists of all characters up to a comment character or unescaped NEWLINE, is the value. make strips both leading and trailing white space in accepting the value.
Subsequent references to the macro, of the forms: $(name) or ${name} are replaced by value. The parentheses or brackets can be omitted in a reference to a macro with a single-character name.
Macro references can contain references to other macros, in which case nested references are expanded first.
Substitutions within macros can be made as follows:
$(name:string1=string2)
where string1 is either a suffix, or a word to be replaced in the macro definition, and string2 is the replacement suffix or word. Words in a macro value are separated by SPACE, TAB, and escaped NEWLINE characters.
Pattern matching replacements can also be applied to macros, with a reference of the form:
$(name: op%os= np%ns)
where op is the existing (old) prefix and os is the existing (old) suffix, np and ns are the new prefix and new suffix, respectively, and the pattern matched by % (a string of zero or more characters), is carried forward from the value being replaced. For example:
PROGRAM=fabricate
DEBUG= $(PROGRAM:%=tmp/%-g)
sets the value of DEBUG to tmp/fabricate-g.
Notice that pattern replacement macro references cannot be used in the dependency list of a pattern matching rule; the % characters are not evaluated independently. Also, any number of % metacharacters can appear after the equal-sign.
Words can be appended to macro values as follows:
macro += word .\|.\|.
When the MAKEFLAGS variable is present in the environment, make takes options from it, in combination with options entered on the command line. make retains this combined value as the MAKEFLAGS macro, and exports it automatically to each command or shell it invokes.
Notice that flags passed by way of MAKEFLAGS are only displayed when the -d, or -dd options are in effect.
The MAKE macro is another special case. It has the value make by default, and temporarily overrides the -n option for any line in which it is referred to. This allows nested invocations of make written as:
$(MAKE) .\|.\|.
to run recursively, with the -n flag in effect for all commands but make. This lets you use make -n to test an entire hierarchy of makefiles.
For compatibility with the 4.2 BSD make, the MFLAGS macro is set from the MAKEFLAGS variable by prepending a -. MFLAGS is not exported automatically.
The SHELL macro, when set to a single-word value such as /usr/bin/csh, indicates the name of an alternate shell to use. The default is /bin/sh. Notice that make executes commands that contain no shell metacharacters itself. Built-in commands, such as dirs in the C shell, are not recognized unless the command line includes a metacharacter (for instance, a semicolon). This macro is neither imported from, nor exported to the environment, regardless of -e. To be sure it is set properly, you must define this macro within every makefile that requires it.
The syntax of the VPATH macro is:
VPATH = [ pathname [ : pathname ] ... ]
VPATH specifies a list of directories to search for the files, which are targets or dependencies, when make is executed. VPATH is also used in order to search for the include files mentioned in the particular makefile.
When processing a target or a dependency or an include directive, make checks the existence of the file with the same name in the current directory. If the file is found to be missing, make searches for this file in the list of directories presented in VPATH (like the PATH variable in the shell). Unlike the PATH variable, VPATH is used in order to search for the files with relative pathnames. When make attempts to apply implicit rules to the target, it also searches for the dependency files using VPATH.
When the file is found using VPATH, internal macros $@, @<, $?, $*, and their alternative forms (with D or F appended) are set in accordance with the name derived from VPATH. For instance, if the target subdir/foo.o is found in the directory /aaa/bbb using VPATH, then the value of the internal macro $@ for this target is /aaa/bbb/subdir/foo.o.
If a target or a dependency file is found using VPATH, then any occurrences of the word that is the same as the target name in the subsequent rules are replaced with the actual name of the target derived from VPATH.
For example:
VPATH=./subdir
file.o : file.c
cc -c file.c -o file.o
If file.c is found in ./subdir, then the command
cc -c ./subdir/file.c -o file.o
are executed.
The following macros are provided for use with cross-compilation: HOST_ARCH
The processor type of the host system. By default, this is the output of the mach(1) command, prepended with -. Under normal circumstances, this value should never be altered by the user.
The machine architecture of the host system. By default, this is the output of the arch(1) command, prepended with -. Under normal circumstances, this value should never be altered by the user.
The processor type of the target system. By default, the output of mach, prepended with -.
There are several dynamically maintained macros that are useful as abbreviations within rules. They are shown here as references; if you were to define them, make would simply override the definition. $*
The basename of the current target, derived as if selected for use with an implicit rule.
The name of a dependency file, derived as if selected for use with an implicit rule.
The name of the current target. This is the only dynamic macro whose value is strictly determined when used in a dependency list. (In which case it takes the form $$@.)
The list of dependencies that are newer than the target. Command-dependency checking is automatically suppressed for lines that contain this macro, just as if the command had been prefixed with a ?. See the description of ?, under Special Character Rules above. You can force this check with the ! command-line prefix.
The name of the library member being processed. (See Library Maintenance below.)
To refer to the $@ dynamic macro within a dependency list, precede the reference with an additional $ character (as in, $$@). Because make assigns $< and $* as it would for implicit rules (according to the suffixes list and the directory contents), they can be unreliable when used within explicit target entries.
These macros can be modified to apply either to the filename part, or the directory part of the strings they stand for, by adding an upper case F or D, respectively (and enclosing the resulting name in parentheses or braces). Thus, $(@D) refers to the directory part of the string $@; if there is no directory part, . is assigned. $(@F) refers to the filename part.
A macro definition of the form:
target-list := macro = value
indicates that when processing any of the targets listed and their dependencies, macro is to be set to the value supplied. Notice that if a conditional macro is referred to in a dependency list, the $ must be delayed (use $$ instead). Also, target-list can contain a % pattern, in which case the macro is conditionally defined for all targets encountered that match the pattern. A pattern replacement reference can be used within the value.
You can temporarily append to a macros value with a conditional definition of the form:
target-list := macro += value
make supplies the macros shown in the table that follows for compilers and their options, host architectures, and other commands. Unless these macros are read in as environment variables, their values are not exported by make. If you run make with any of these set in the environment, it is a good idea to add commentary to the makefile to indicate what value each is expected to take. If -r is in effect, make does not read the default makefile (./make.rules or /usr/share/lib/make/make.rules) in which these macro definitions are supplied.
Table of Predefined Macros |
Use Macro Default Value |
Library AR ar |
Archives ARFLAGS rv |
Assembler AS as |
Commands ASFLAGS |
COMPILE.s $(AS) $(ASFLAGS) |
COMPILE.S $(CC) $(ASFLAGS) $(CPPFLAGS) -c |
C CC cc |
Compiler CFLAGS |
Commands CPPFLAGS |
COMPILE.c $(CC) $(CFLAGS) $(CPPFLAGS) -c |
LINK.c $(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) |
C++ CCC CC |
Compiler CCFLAGS CFLAGS |
Commands CPPFLAGS |
COMPILE.cc $(CCC) $(CCFLAGS) $(CPPFLAGS) -c |
LINK.cc $(CCC) $(CCFLAGS) $(CPPFLAGS) $(LDFLAGS) |
COMPILE.C $(CCC) $(CCFLAGS) $(CPPFLAGS) -c |
LINK.C $(CCC) $(CCFLAGS) $(CPPFLAGS) $(LDFLAGS) |
FORTRAN 77 FC f77 |
Compiler FFLAGS |
Commands COMPILE.f $(FC) $(FFLAGS) -c |
LINK.f $(FC) $(FFLAGS) $(LDFLAGS) |
COMPILE.F $(FC) $(FFLAGS) $(CPPFLAGS) -c |
LINK.F $(FC) $(FFLAGS) $(CPPFLAGS) $(LDFLAGS) |
FORTRAN 90 FC f90 |
Compiler F90FLAGS |
Commands COMPILE.f90 $(F90C) $(F90FLAGS) -c |
LINK.f90 $(F90C) $(F90FLAGS) $(LDFLAGS) |
COMPILE.ftn $(F90C) $(F90FLAGS) $(CPPFLAGS) -c |
LINK.ftn |
$(F90C) $(F90FLAGS) $(CPPFLAGS) $(LDFLAGS) |
Link Editor LD ld |
Command LDFLAGS |
lex LEX lex |
Command LFLAGS |
LEX.l $(LEX) $(LFLAGS) -t |
lint LINT lint |
Command LINTFLAGS |
LINT.c $(LINT) $(LINTFLAGS) $(CPPFLAGS) |
Modula 2 M2C m2c |
Commands M2FLAGS |
MODFLAGS |
DEFFLAGS |
COMPILE.def $(M2C) $(M2FLAGS) $(DEFFLAGS) |
COMPILE.mod $(M2C) $(M2FLAGS) $(MODFLAGS) |
Pascal PC pc |
Compiler PFLAGS |
Commands COMPILE.p $(PC) $(PFLAGS) $(CPPFLAGS) -c |
LINK.p $(PC) $(PFLAGS) $(CPPFLAGS) $(LDFLAGS) |
Ratfor RFLAGS |
Compilation COMPILE.r $(FC) $(FFLAGS) $(RFLAGS) -c |
Commands LINK.r $(FC) $(FFLAGS) $(RFLAGS) $(LDFLAGS) |
rm Command RM rm -f |
sccs SCCSFLAGS |
Command SCCSGETFLAGS -s |
yacc YACC yacc |
Command YFLAGS |
YACC.y $(YACC) $(YFLAGS) |
Suffixes List SUFFIXES |
.o .c .c~ .cc .cc~ .y .y~ .l .l~ .s .s~ .sh .sh~ .S .S~ .ln .h .h~ .f .f~ .F .F~ .mod .mod~ .sym .def .def~ .p .p~ .r .r~ .cps .cps~ .C .C~ .Y .Y~ .L .L .f90 .f90~ .ftn .ftn~ |
When a target has no entry in the makefile, make attempts to determine its class (if any) and apply the rule for that class. An implicit rule describes how to build any target of a given class, from an associated dependency file. The class of a target can be determined either by a pattern, or by a suffix; the corresponding dependency file (with the same basename) from which such a target might be built. In addition to a predefined set of implicit rules, make allows you to define your own, either by pattern, or by suffix.
A target entry of the form:
tp%ts:\|dp%ds rule
is a pattern matching rule, in which tp is a target prefix, ts is a target suffix, dp is a dependency prefix, and ds is a dependency suffix (any of which can be null). The % stands for a basename of zero or more characters that is matched in the target, and is used to construct the name of a dependency. When make encounters a match in its search for an implicit rule, it uses the rule in that target entry to build the target from the dependency file. Pattern-matching implicit rules typically make use of the $@ and $< dynamic macros as placeholders for the target and dependency names. Other, regular dependencies can occur in the dependency list; however, none of the regular dependencies can contain %. An entry of the form:
tp%ts:\|[dependency .\|.\|.\|] dp%ds\|[dependency .\|.\|.\|] rule
is a valid pattern matching rule.
When no pattern matching rule applies, make checks the target name to see if it ends with a suffix in the known suffixes list. If so, make checks for any suffix rules, as well as a dependency file with same root and another recognized suffix, from which to build it.
The target entry for a suffix rule takes the form:
DsTs: rule
where Ts is the suffix of the target, Ds is the suffix of the dependency file, and rule is the rule for building a target in the class. Both Ds and Ts must appear in the suffixes list. (A suffix need not begin with a . to be recognized.)
A suffix rule with only one suffix describes how to build a target having a null (or no) suffix from a dependency file with the indicated suffix. For instance, the .c rule could be used to build an executable program named file from a C source file named file.c. If a target with a null suffix has an explicit dependency, make omits the search for a suffix rule.
Table of Standard Implicit (Suffix) Rules for Assembly Files |
Implicit Rule Name Command Line |
.s.o $(COMPILE.s) -o $@ $< |
.s.a $(COMPILE.s) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.s~.o $(GET) $(GFLAGS) -p $< > $*.s |
$(COMPILE.s) -o $@ $*.s |
.S.o $(COMPILE.S) -o $@ $< |
.S.a $(COMPILE.S) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.S~.o $(GET) $(GFLAGS) -p $< > $*.S |
$(COMPILE.S) -o $@ $*.S |
.S~.a $(GET) $(GFLAGS) -p $< > $*.S |
$(COMPILE.S) -o $% $*.S |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for C Files |
Implicit Rule Name Command Line |
.c $(LINK.c) -o $@ $< $(LDLIBS) |
.c.ln $(LINT.c) $(OUTPUT_OPTION) -i $< |
.c.o $(COMPILE.c) $(OUTPUT_OPTION) $< |
.c.a $(COMPILE.c) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.c~ $(GET) $(GFLAGS) -p $< > $*.c |
$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $*.c |
.c~.o $(GET) $(GFLAGS) -p $< > $*.c |
$(CC) $(CFLAGS) -c $*.c |
.c~.ln $(GET) $(GFLAGS) -p $< > $*.c |
$(LINT.c) $(OUTPUT_OPTION) -c $*.c |
.c~.a $(GET) $(GFLAGS) -p $< > $*.c |
$(COMPILE.c) -o $% $*.c |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for C++ Files |
Implicit Rule Name Command Line |
.cc $(LINK.cc) -o $@ $< $(LDLIBS) |
.cc.o $(COMPILE.cc) $(OUTPUT_OPTION) $< |
.cc.a $(COMPILE.cc) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.cc~ $(GET) $(GFLAGS) -p $< > $*.cc |
$(LINK.cc) -o $@ $*.cc $(LDLIBS) |
.cc.o $(COMPILE.cc) $(OUTPUT_OPTION) $< |
.cc~.o $(GET) $(GFLAGS) -p $< > $*.cc |
$(COMPILE.cc) $(OUTPUT_OPTION) $*.cc |
.cc.a $(COMPILE.cc) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.cc~.a $(GET) $(GFLAGS) -p $< > $*.cc |
$(COMPILE.cc) -o $% $*.cc |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.C $(LINK.C) -o $@ $< $(LDLIBS) |
.C~ $(GET) $(GFLAGS) -p $< > $*.C |
$(LINK.C) -o $@ $*.C $(LDLIBS) |
.C.o $(COMPILE.C) $(OUTPUT_OPTION) $< |
.C~.o $(GET) $(GFLAGS) -p $< > $*.C |
$(COMPILE.C) $(OUTPUT_OPTION) $*.C |
.C.a $(COMPILE.C) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.C~.a $(GET) $(GFLAGS) -p $< > $*.C |
$(COMPILE.C) -o $% $*.C |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for FORTRAN 77 Files |
Implicit Rule Name Command Line |
.f $(LINK.f) -o $@ $< $(LDLIBS) |
.f.o $(COMPILE.f) $(OUTPUT_OPTION) $< |
.f.a $(COMPILE.f) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.f $(LINK.f) -o $@ $< $(LDLIBS) |
.f~ $(GET) $(GFLAGS) -p $< > $*.f |
$(FC) $(FFLAGS) $(LDFLAGS) -o $@ $*.f |
.f~.o $(GET) $(GFLAGS) -p $< > $*.f |
$(FC) $(FFLAGS) -c $*.f |
.f~.a $(GET) $(GFLAGS) -p $< > $*.f |
$(COMPILE.f) -o $% $*.f |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.F $(LINK.F) -o $@ $< $(LDLIBS) |
.F.o $(COMPILE.F) $(OUTPUT_OPTION) $< |
.F.a $(COMPILE.F) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.F~ $(GET) $(GFLAGS) -p $< > $*.F |
$(FC) $(FFLAGS) $(LDFLAGS) -o $@ $*.F |
.F~.o $(GET) $(GFLAGS) -p $< > $*.F |
$(FC) $(FFLAGS) -c $*.F |
.F~.a $(GET) $(GFLAGS) -p $< > $*.F |
$(COMPILE.F) -o $% $*.F |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for FORTRAN 90 Files |
Implicit Rule Name Command Line |
.f90 $(LINK.f90) -o $@ $< $(LDLIBS) |
.f90~ $(GET) $(GFLAGS) -p $< > $*.f90 |
$(LINK.f90) -o $@ $*.f90 $(LDLIBS) |
.f90.o $(COMPILE.f90) $(OUTPUT_OPTION) $< |
.f90~.o $(GET) $(GFLAGS) -p $< > $*.f90 |
$(COMPILE.f90) $(OUTPUT_OPTION) $*.f90 |
.f90.a $(COMPILE.f90) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.f90~.a $(GET) $(GFLAGS) -p $< > $*.f90 |
$(COMPILE.f90) -o $% $*.f90 |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.ftn $(LINK.ftn) -o $@ $< $(LDLIBS) |
.ftn~ $(GET) $(GFLAGS) -p $< > $*.ftn |
$(LINK.ftn) -o $@ $*.ftn $(LDLIBS) |
.ftn.o $(COMPILE.ftn) $(OUTPUT_OPTION) $< |
.ftn~.o $(GET) $(GFLAGS) -p $< > $*.ftn |
$(COMPILE.ftn) $(OUTPUT_OPTION) $*.ftn |
.ftn.a $(COMPILE.ftn) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.ftn~.a $(GET) $(GFLAGS) -p $< > $*.ftn |
$(COMPILE.ftn) -o $% $*.ftn |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for lex Files |
Implicit Rule Name Command Line |
.l $(RM) $*.c |
$(LEX.l) $< > $*.c |
$(LINK.c) -o $@ $*.c $(LDLIBS) |
$(RM) $*.c |
.l.c $(RM) $@ |
$(LEX.l) $< > $@ |
.l.ln $(RM) $*.c |
$(LEX.l) $< > $*.c |
$(LINT.c) -o $@ -i $*.c |
$(RM) $*.c |
.l.o $(RM) $*.c |
$(LEX.l) $< > $*.c |
$(COMPILE.c) -o $@ $*.c |
$(RM) $*.c |
.l~ $(GET) $(GFLAGS) -p $< > $*.l |
$(LEX) $(LFLAGS) $*.l |
$(CC) $(CFLAGS) -c lex.yy.c |
rm -f lex.yy.c |
mv lex.yy.c $@ |
.l~.c $(GET) $(GFLAGS) -p $< > $*.l |
$(LEX) $(LFLAGS) $*.l |
mv lex.yy.c $@ |
.l~.ln $(GET) $(GFLAGS) -p $< > $*.l |
$(RM) $*.c |
$(LEX.l) $*.l > $*.c |
$(LINT.c) -o $@ -i $*.c |
$(RM) $*.c |
.l~.o $(GET) $(GFLAGS) -p $< > $*.l |
$(LEX) $(LFLAGS) $*.l |
$(CC) $(CFLAGS) -c lex.yy.c |
rm -f lex.yy.c |
mv lex.yy.c $@ |
Table of Standard Implicit (Suffix) Rules for Modula 2 Files |
Implicit Rule Name Command Line |
.mod $(COMPILE.mod) -o $@ -e $@ $< |
.mod.o $(COMPILE.mod) -o $@ $< |
.def.sym $(COMPILE.def) -o $@ $< |
.def~.sym $(GET) $(GFLAGS) -p $< > $*.def |
$(COMPILE.def) -o$@ $*.def |
.mod~ $(GET) $(GFLAGS) -p $< > $*.mod |
$(COMPILE.mod) -o $@ -e $@ $*.mod |
.mod~.o $(GET) $(GFLAGS) -p $< > $*.mod |
$(COMPILE.mod) -o $@ $*.mod |
.mod~.a $(GET) $(GFLAGS) -p $< > $*.mod |
$(COMPILE.mod) -o $% $*.mod |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for NeWS Files |
Implicit Rule Name Command Line |
.cps.h cps $*.cps |
.cps~.h $(GET) $(GFLAGS) -p $< > $*.cps |
$(CPS) $(CPSFLAGS) $*.cps |
Table of Standard Implicit (Suffix) Rules for Pascal Files |
Implicit Rule Name Command Line |
.p $(LINK.p) -o $@ $< $(LDLIBS) |
.p.o $(COMPILE.p) $(OUTPUT_OPTION) $< |
.p~ $(GET) $(GFLAGS) -p $< > $*.p |
$(LINK.p) -o $@ $*.p $(LDLIBS) |
.p~.o $(GET) $(GFLAGS) -p $< > $*.p |
$(COMPILE.p) $(OUTPUT_OPTION) $*.p |
.p~.a $(GET) $(GFLAGS) -p $< > $*.p |
$(COMPILE.p) -o $% $*.p |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for Ratfor Files |
Implicit Rule Name Command Line |
.r $(LINK.r) -o $@ $< $(LDLIBS) |
.r.o $(COMPILE.r) $(OUTPUT_OPTION) $< |
.r.a $(COMPILE.r) -o $% $< |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
.r~ $(GET) $(GFLAGS) -p $< > $*.r |
$(LINK.r) -o $@ $*.r $(LDLIBS) |
.r~.o $(GET) $(GFLAGS) -p $< > $*.r |
$(COMPILE.r) $(OUTPUT_OPTION) $*.r |
.r~.a $(GET) $(GFLAGS) -p $< > $*.r |
$(COMPILE.r) -o $% $*.r |
$(AR) $(ARFLAGS) $@ $% |
$(RM) $% |
Table of Standard Implicit (Suffix) Rules for SCCS Files |
Implicit Rule Name Command Line |
.SCCS_GET |
sccs $(SCCSFLAGS) get $(SCCSGETFLAGS) $@ -G$@ |
.SCCS_GET_POSIX sccs $(SCCSFLAGS) get $(SCCSGETFLAGS) $@ |
.GET_POSIX $(GET) $(GFLAGS) s.$@ |
Table of Standard Implicit (Suffix) Rules for Shell Scripts |
Implicit Rule Name Command Line |
.sh cat $< >$@ |
chmod +x $@ |
.sh~ $(GET) $(GFLAGS) -p $< > $*.sh |
cp $*.sh $@ |
chmod a+x $@ |
Table of Standard Implicit (Suffix) Rules for yacc Files |
Implicit Rule Name Command Line |
.y $(YACC.y) $< |
$(LINK.c) -o $@ y.tab.c $(LDLIBS) |
$(RM) y.tab.c |
.y.c $(YACC.y) $< |
mv y.tab.c $@ |
.y.ln $(YACC.y) $< |
$(LINT.c) -o $@ -i y.tab.c |
$(RM) y.tab.c |
.y.o $(YACC.y) $< |
$(COMPILE.c) -o $@ y.tab.c |
$(RM) y.tab.c |
.y~ $(GET) $(GFLAGS) -p $< > $*.y |
$(YACC) $(YFLAGS) $*.y |
$(COMPILE.c) -o $@ y.tab.c |
$(RM) y.tab.c |
.y~.c $(GET) $(GFLAGS) -p $< > $*.y |
$(YACC) $(YFLAGS) $*.y |
mv y.tab.c $@ |
.y~.ln $(GET) $(GFLAGS) -p $< > $*.y |
$(YACC.y) $*.y |
$(LINT.c) -o $@ -i y.tab.c |
$(RM) y.tab.c |
.y~.o $(GET) $(GFLAGS) -p $< > $*.y |
$(YACC) $(YFLAGS) $*.y |
$(CC) $(CFLAGS) -c y.tab.c |
rm -f y.tab.c |
mv y.tab.o $@ |
make reads in the standard set of implicit rules from the file /usr/share/lib/make/make.rules, unless -r is in effect, or there is a make.rules file in the local directory that does not include that file.
The suffixes list is given as the list of dependencies for the .SUFFIXES: special-function target. The default list is contained in the SUFFIXES macro (See Table of Predefined Macros for the standard list of suffixes). You can define additional .SUFFIXES: targets; a .SUFFIXES target with no dependencies clears the list of suffixes. Order is significant within the list; make selects a rule that corresponds to the target's suffix and the first dependency-file suffix found in the list. To place suffixes at the head of the list, clear the list and replace it with the new suffixes, followed by the default list:
.SUFFIXES:
.SUFFIXES: suffixes $(SUFFIXES)
A tilde (~) indicates that if a dependency file with the indicated suffix (minus the ~) is under SCCS its most recent version should be retrieved, if necessary, before the target is processed.
A target name of the form:
lib(member ...)
refers to a member, or a space-separated list of members, in an ar(1) library.
The dependency of the library member on the corresponding file must be given as an explicit entry in the makefile. This can be handled by a pattern matching rule of the form:
lib(%.s): %.s
where .s is the suffix of the member; this suffix is typically .o for object libraries.
A target name of the form:
lib((symbol))
refers to the member of a randomized object library that defines the entry point named symbol.
Command lines are executed one at a time, each by its own process or shell. Shell commands, notably cd, are ineffectual across an unescaped NEWLINE in the makefile. A line is printed (after macro expansion) just before being executed. This is suppressed if it starts with a @, if there is a .SILENT: entry in the makefile, or if make is run with the -s option. Although the -n option specifies printing without execution, lines containing the macro $(MAKE) are executed regardless, and lines containing the @ special character are printed. The -t (touch) option updates the modification date of a file without executing any rules. This can be dangerous when sources are maintained by more than one person.
make invokes the shell with the -e (exit-on-errors) argument. Thus, with semicolon-separated command sequences, execution of the later commands depends on the success of the former. This behavior can be overridden by starting the command line with a \|-, or by writing a shell script that returns a non-zero status only as it finds appropriate.
To use the Bourne shell if control structure for branching, use a command line of the form:
if expression ; \e then command ; \e ... ; \e else command; \e ... ; \e fi
Although composed of several input lines, the escaped NEWLINE characters insure that make treats them all as one (shell) command line.
To use the Bourne shell for control structure for loops, use a command line of the form:
for var in list ; \e do command; \e ... ; \edone
To refer to a shell variable, use a double-dollar-sign ($$). This prevents expansion of the dollar-sign by make.
To incorporate the standard output of a shell command in a macro, use a definition of the form:
MACRO\|:sh =command
The command is executed only once, standard error output is discarded, and NEWLINE characters are replaced with SPACEs. If the command has a non-zero exit status, make halts with an error.
To capture the output of a shell command in a macro reference, use a reference of the form:
$(MACRO\|:sh)
where MACRO is the name of a macro containing a valid Bourne shell command line. In this case, the command is executed whenever the reference is evaluated. As with shell command substitutions, the reference is replaced with the standard output of the command. If the command has a non-zero exit status, make halts with an error.
In contrast to commands in rules, the command is not subject for macro substitution; therefore, a dollar sign ($) need not be replaced with a double dollar sign ($$).
INT, SIGTERM, and QUIT signals received from the keyboard halt make and remove the target file being processed unless that target is in the dependency list for .PRECIOUS:.
Example 1 Defining dependencies
This makefile says that pgm depends on two files a.o and b.o, and that they in turn depend on their corresponding source files (a.c and b.c) along with a common file incl.h:
pgm: a.o b.o $(LINK.c) -o $@a.o b.o a.o: incl.h a.c cc -c a.c b.o: incl.h b.c cc -c b.c
Example 2 Using implicit rules
The following makefile uses implicit rules to express the same dependencies:
pgm: a.o b.o cc a.o b.o -o pgm a.o b.o: incl.h
See environ(5) for descriptions of the following environment variables that affect the execution of make: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES, and NLSPATH. DMAKE_MAX_JOBS
The maximum number of jobs that each instance of make should run.
If YES adjust the maximum number of jobs each instance of make runs based on system load. If NO do not
Adjusts the format of output from make when executing jobs in parallel. If the value is TEXT1 make will print the hostname and the command executed once when the job begins, and again preceding any output from that job. If the value is TEXT2 make will only print the command and its output only once, when execution is complete.
Specify whether jobs should be executed in serial, or parallel. Equivalent to passing the -m\FR option.
This environment variable has the same effect as the .KEEP_STATE: special-function target. It enables command dependencies, hidden dependencies and writing of the state file.
This environment variable causes make to invoke the generic System V version of make (/usr/lib/svr4.make). See sysV-make(1).
This variable is interpreted as a character string representing a series of option characters to be used as the default options. The implementation accepts both of the following formats (but need not accept them when intermixed):
1. The characters are option letters without the leading hyphens or blank character separation used on a command line.
2. The characters are formatted in a manner similar to a portion of the make command line: options are preceded by hyphens and blank-character-separated. The macro=name macro definition operands can also be included. The difference between the contents of MAKEFLAGS and the command line is that the contents of the variable is not subjected to the word expansions associated with parsing the command line values. See wordexp(3C). When the command-line options -f or -p are used, they take effect regardless of whether they also appear in MAKEFLAGS. If they otherwise appear in MAKEFLAGS, the result is undefined.
Provides a directory to be used to search for SCCS files not found in the current directory. In all of the following cases, the search for SCCS files is made in the directory SCCS in the identified directory. If the value of PROJECTDIR begins with a slash, it shall be considered an absolute pathname. Otherwise, the value of PROJECTDIR is treated as a user name and that user's initial working directory shall be examined for a subdirectory src or source. If such a directory is found, it shall be used. Otherwise, the value is used as a relative pathname. If PROJECTDIR is not set or has a null value, the search for SCCS files shall be made in the directory SCCS in the current directory. The setting of PROJECTDIR affects all files listed in the remainder of this utility description for files with a component named SCCS.
When the -q option is specified, the make utility exits with one of the following values: 0
Successful completion.
The target was not up-to-date.
An error occurred.
When the -q option is not specified, the make utility exits with one of the following values: 0
Successful completion
An error occurred
Makefile
current version(s) of make description file
s.Makefile
SCCS history files for the above makefile(s) in the current directory
SCCS history files for the above makefile(s)
default file for user-defined targets, macros, and implicit rules
makefile for standard implicit rules and macros (not read if make.rules is)
state file in the local directory
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE ATTRIBUTE VALUE |
Interface Stability Committed |
Standard See standards(5). |
ar(1), arch(1), cd(1), cpp(1), lex(1), mach(1), sccs-get(1), sh(1), sysV-make(1), yacc(1), wordexp(3C), passwd(4), attributes(5), environ(5), POSIX.2(5), standards(5)
Solaris Advanced User's Guide
There is no makefile entry for target, and none of make's implicit rules apply (there is no dependency file with a suffix in the suffixes list, or the target's suffix is not in the list).
make was interrupted while building target. Rather than leaving a partially-completed version that is newer than its dependencies, make removes the file named target.
make was interrupted while building target and target was not present in the directory.
make was interrupted while building target, which was not removed for the indicated reason.
The makefile indicated in an include directive was not found, or was inaccessible.
A reference to the macro being defined was found in the definition.
You used the .KEEP_STATE: target, but do not have write permission on the state file.
The previous shell command returned a nonzero error code.
The previous shell command was aborted due to a signal. If - core dumped appears after the message, a core file was created.
Displayed only when -d is in effect, this message indicates that two or more parallel targets currently being processed depend on a target which is built differently for each by virtue of conditional macros. Since the target cannot simultaneously satisfy both dependency relationships, it is conflicted.
Some commands return nonzero status inappropriately; to overcome this difficulty, prefix the offending command line in the rule with a -.
Filenames with the characters =, :, or @, do not work.
You cannot build file.o from lib(file.o).
Options supplied by MAKEFLAGS should be reported for nested make commands. Use the -d option to find out what options the nested command picks up from MAKEFLAGS.
This version of make is incompatible in certain respects with previous versions:
The -d option output is much briefer in this version. -dd now produces the equivalent voluminous output.
make attempts to derive values for the dynamic macros $*, $<, and $?, while processing explicit targets. It uses the same method as for implicit rules; in some cases this can lead either to unexpected values, or to an empty value being assigned. (Actually, this was true for earlier versions as well, even though the documentation stated otherwise.)
make no longer searches for SCCS history (s.) files.
Suffix replacement in macro references are now applied after the macro is expanded.
There is no guarantee that makefiles created for this version of make work with earlier versions.
If there is no make.rules file in the current directory, and the file /usr/share/lib/make/make.rules is missing, make stops before processing any targets. To force make to run anyway, create an empty make.rules file in the current directory.
Once a dependency is made, make assumes the dependency file is present for the remainder of the run. If a rule subsequently removes that file and future targets depend on its existence, unexpected errors can result.
When hidden dependency checking is in effect, the $? macro's value includes the names of hidden dependencies. This can lead to improper filename arguments to commands when $? is used in a rule.
Pattern replacement macro references cannot be used in the dependency list of a pattern matching rule.
Unlike previous versions, this version of make strips a leading ./ from the value of the $@ dynamic macro.
With automatic SCCS retrieval, this version of make does not support tilde suffix rules.
The only dynamic macro whose value is strictly determined when used in a dependency list is $@ (takes the form $$@).
make invokes the shell with the -e argument. This cannot be inferred from the syntax of the rule alone.