注意:这个答案已经更新到GNU make v4.3仍然可以工作——如果你遇到什么问题，请告诉我们。
本文试图改进Brent Bradburn的伟大方法，如下所示:
使用更健壮的命令来提取目标名称，这有望防止任何误报(还消除了不必要的sh -c)
并不总是以当前目录中的makefile为目标;尊重使用-f <file>显式指定的makefile
不包括隐藏目标——按照惯例，这些目标的名称既不是以字母开头，也不是以数字开头
只对付一个假目标
使用@作为命令的前缀，防止命令在执行前被回显
奇怪的是，GNU make没有列出makefile中定义的目标名称的特性。虽然-p选项生成包含所有目标的输出，但它将这些目标隐藏在许多其他信息中，并执行默认目标(可以使用-f/dev/null来抑制)。
将下面的规则放在一个makefile中，让GNU make实现一个目标命名列表，简单地按字母顺序列出所有目标名称-即:调用为make列表:
.PHONY: list
list:
@LC_ALL=C $(MAKE) -pRrq -f $(lastword $(MAKEFILE_LIST)) : 2>/dev/null | awk -v RS= -F: '/(^|\n)# Files(\n|$$)/,/(^|\n)# Finished Make data base/ {if ($$1 !~ "^[#.]") {print $$1}}' | sort | egrep -v -e '^[^[:alnum:]]' -e '^$@$$'
重要提示:在粘贴此文件时，确保最后一行缩进了恰好1个实际的制表符字符。(空格无效)。
Note that sorting the resulting list of targets is the best option, since not sorting doesn't produce a helpful ordering in that the order in which the targets appear in the makefile is not preserved.
Also, the sub-targets of a rule comprising multiple targets are invariably output separately and will therefore, due to sorting, usually not appear next to one another; e.g., a rule starting with a z: will not have targets a and z listed next to each other in the output, if there are additional targets.
规则解释:
.PHONY: list
declares target list a phony target, i.e., one not referring to a file, which should therefore have its recipe invoked unconditionally
LC_ALL=C makes sure that make's output in in English, as parsing of the output relies on that.Tip of the hat to Bastian Bittorf
$(MAKE) -pRrq -f $(lastword $(MAKEFILE_LIST)) : 2>/dev/null
Invokes make again in order to print and parse the database derived from the makefile:
-p prints the database
-Rr suppresses inclusion of built-in rules and variables
-q only tests the up-to-date-status of a target (without remaking anything), but that by itself doesn't prevent execution of recipe commands in all cases; hence:
-f $(lastword $(MAKEFILE_LIST)) ensures that the same makefile is targeted as in the original invocation, regardless of whether it was targeted implicitly or explicitly with -f ....
Caveat: This will break if your makefile contains include directives; to address this, define variable THIS_FILE := $(lastword $(MAKEFILE_LIST)) before any include directives and use -f $(THIS_FILE) instead.
: is a deliberately invalid target that is meant to ensure that no commands are executed; 2>/dev/null suppresses the resulting error message. Note: This relies on -p printing the database nonetheless, which is the case as of GNU make 3.82. Sadly, GNU make offers no direct option to just print the database, without also executing the default (or given) task; if you don't need to target a specific Makefile, you may use make -p -f/dev/null, as recommended in the man page.
-v RS=
This is an awk idiom that breaks the input into blocks of contiguous non-empty lines.
/(^|\n)# Files(\n|$$)/,/(^|\n)# Finished Make data base/
Matches the range of lines in the output that contains all targets, across paragraphs - by limiting parsing to this range, there is no need to deal with false positives from other output sections.
Note: Between make versions 3.x and 4.3, paragraph structuring in make's output changed, so (^|\n) / (\n|$$) ensures that the lines that identify the start and the end of the cross-paragraph range of lines of interest are detected irrespective of whether they occur at the start or inside / at the end of a paragraph.
if ($$1 !~ "^[#.]")
Selectively ignores blocks:
# ... ignores non-targets, whose blocks start with # Not a target:
. ... ignores special targets
All other blocks should each start with a line containing only the name of an explicitly defined target followed by :
egrep -v -e '^[^[:alnum:]]' -e '^$@$$' removes unwanted targets from the output:
'^[^[:alnum:]]' ... excludes hidden targets, which - by convention - are targets that start neither with a letter nor a digit.
'^$@$$' ... excludes the list target itself
然后运行make list，打印所有目标，每个目标在自己的行上;您可以通过管道连接到xargs来创建一个以空格分隔的列表。
