我使用过一些rake(一个Ruby make程序)，它有一个选项，可以获得所有可用目标的列表，例如
> rake --tasks
rake db:charset # retrieve the charset for your data...
rake db:collation # retrieve the collation for your da...
rake db:create # Creates the databases defined in y...
rake db:drop # Drops the database for your curren...
...
但是在GNU make中似乎没有这样做的选项。
显然，代码几乎已经有了，截至2007年- http://www.mail-archive.com/help-make@gnu.org/msg06434.html。
不管怎样，我做了一个小hack来从makefile中提取目标，你可以将它包含在makefile中。
list:
@grep '^[^#[:space:]].*:' Makefile
它会给你一个已定义目标的列表。这只是一个开始——例如，它并没有过滤掉依赖关系。
> make list
list:
copy:
run:
plot:
turnin:
对于讨厌AWK的人来说，为了简单起见，这个精巧的设计适合我:
help:
make -qpRr $(lastword $(MAKEFILE_LIST)) | egrep -v '(^(\.|:|#|\s|$)|=)' | cut -d: -f1
(对于在Makefile外部使用，只需删除$(最后一个词…)或将其替换为Makefile路径)。
This solution will not work if you have "interesting" rule names but will work well for most simple setups. The main downside of a make -qp based solution is (as in other answers here) that if the Makefile defines variable values using functions - they will still be executed regardless of -q, and if using $(shell ...) then the shell command will still be called and its side effects will happen. In my setup often the side effects of running shell functions is unwanted output to standard error, so I add 2>/dev/null after the make command.
专注于描述make目标的简单语法，并有一个干净的输出，我选择了以下方法:
help:
@grep -B1 -E "^[a-zA-Z0-9_-]+\:([^\=]|$$)" Makefile \
| grep -v -- -- \
| sed 'N;s/\n/###/' \
| sed -n 's/^#: \(.*\)###\(.*\):.*/\2###\1/p' \
| column -t -s '###'
#: Starts the container stack
up: a b
command
#: Pulls in new container images
pull: c d
another command
make-target-not-shown:
# this does not count as a description, so leaving
# your implementation comments alone, e.g TODOs
also-not-shown:
因此，将上面的文件作为Makefile来处理并运行它会给您带来类似于
> make help
up Starts the container stack
pull Pulls in new container images
命令链的解释:
First, grep all targets and their preceeding line, see https://unix.stackexchange.com/a/320709/223029.
Then, get rid of the group separator, see https://stackoverflow.com/a/2168139/1242922.
Then, we collapse each pair of lines to parse it later, see https://stackoverflow.com/a/9605559/1242922.
Then, we parse for valid lines and remove those which do not match, see https://stackoverflow.com/a/8255627/1242922, and also give the output our desired order: command, then description.
Lastly, we arrange the output like a table.
正如mklement0所指出的，GNU-make中缺少列出所有Makefile目标的功能，他的回答和其他回答提供了实现这一点的方法。
然而，最初的帖子也提到了rake，它的任务开关做的事情与仅仅在rakefile中列出所有任务略有不同。Rake只会给您一个有相关描述的任务列表。没有描述的任务将不会被列出。这使得作者既可以提供定制的帮助描述，也可以省略某些目标的帮助。
如果您想模拟rake的行为，为每个目标提供描述，有一个简单的技术可以做到这一点:在注释中嵌入您想列出的每个目标的描述。
你可以把描述放在目标旁边，或者像我经常做的那样，放在目标上面的PHONY规范旁边，就像这样:
.PHONY: target1 # Target 1 help text
target1: deps
[... target 1 build commands]
.PHONY: target2 # Target 2 help text
target2:
[... target 2 build commands]
...
.PHONY: help # Generate list of targets with descriptions
help:
@grep '^.PHONY: .* #' Makefile | sed 's/\.PHONY: \(.*\) # \(.*\)/\1 \2/' | expand -t20
它会屈服
$ make help
target1 Target 1 help text
target2 Target 2 help text
...
help Generate list of targets with descriptions
你也可以在这里找到一个简短的代码示例。
同样，这不能解决在Makefile中列出所有目标的问题。例如，如果您有一个大的Makefile，它可能是生成的或由其他人编写的，并且您想要一种快速的方法来列出它的目标，而不需要深入研究它，那么这将没有帮助。
但是，如果您正在编写Makefile，并且希望以一致的、自记录的方式生成帮助文本，则此技术可能会有用。
对于讨厌AWK的人来说，为了简单起见，这个精巧的设计适合我:
help:
make -qpRr $(lastword $(MAKEFILE_LIST)) | egrep -v '(^(\.|:|#|\s|$)|=)' | cut -d: -f1
(对于在Makefile外部使用，只需删除$(最后一个词…)或将其替换为Makefile路径)。
This solution will not work if you have "interesting" rule names but will work well for most simple setups. The main downside of a make -qp based solution is (as in other answers here) that if the Makefile defines variable values using functions - they will still be executed regardless of -q, and if using $(shell ...) then the shell command will still be called and its side effects will happen. In my setup often the side effects of running shell functions is unwanted output to standard error, so I add 2>/dev/null after the make command.
