''.PHONY'' für targets die keine Dateien erzeugen und und immer ausgeführt werden sollen / ''FORCE'' für targets die files erzeugen und immer ausgeführt werden sollen (''FORCE'' selbst ist nicht ''.PHONY'') [[https://github.com/RIOT-OS/RIOT/pull/9623|Quelle]]

====== GNU Make cheat scheet ======
===== Variables =====
[[https://www.gnu.org/software/make/manual/html_node/Automatic-Variables.html|Ofiziell]].
| ''$@'' | ''**target**: a b a c'' |
| ''$%'' | The target member name, when the target is an archive member. |
| ''$<'' | ''target: **a** b a c'' |
| ''$?'' | ''target: a **b** a **c**'' (newer prerequisites) |
| ''$^'' | ''target: **a** **b** a **c**'' |
| ''$+'' | ''target: **a** **b** **a** **c**'' |
| ''$*'' | The stem with which an implicit rule matches. |
| ''$|'' | ''target: a b a c | **d** **e** **f**'' |
... da fehlen welche

| ''CPPFLAGS'' | Compiler, alle Sprachen (z.B. ''-I...'') |
| ''CFLAGS''   | Compiler, nur C (z.B. ''-std=...'') |
| ''CXXFLAGS'' | Compiler, nur C++ |

===== Functions =====
[[https://www.gnu.org/software/make/manual/html_node/Text-Functions.html|Ofiziell]].

| ''$(**subst** from,to,text)''            | Fixed string replacement. |
| ''$(**patsubst** %-from,%to,text)''      | %-Pattern replacement. \\ Alternative 1: ''$(var:%-from=%-to)'' \\ Alternative 2: ''$(var:suffix=replacement)'' |
| ''$(**strip** string)''                  | Remove whitespace at the ends (like ''trim''). |
| ''$(**findstring** find,text)''          | Return ''"find"'' or ''""''. |
| ''$(**filter** pattern...,word...)''     | Return //word// which matches any %-pattern |
| ''$(**filter-out** pattern...,word...)'' | Return //word// which mateches none %-pattern. |
| ''$(**sort** word...)'' | 1) Sort words, 2) removing duplicates. |
| ''$(**dir** names...)''                  | Extract the directory part of each file name. |
| ''$(**notdir** names...)''               | Extract the non-directory part of each file name. |
| ''$(**suffix** names...)''               | Extract the suffix (the last dot and following characters) of each file name. |
| ''$(**basename** names...)''             | Extract the base name (name without suffix) of each file name. |
| ''$(**addsuffix** suffix,names...)''     | Append suffix to each word in names. |
| ''$(**addprefix** prefix,names...)''     | Prepend prefix to each word in names. |
| ''$(**join** list1,list2)''              | Join two parallel lists of words. |
| ''$(**word** n,word...)''                | The //n//th word. |
| ''$(**firstword** word...)''             | The //1//th word. |
| ''$(**wordlist** s,e,word...)''          | The //s//th ... //e//th word. |
| ''$(**words** word...)''                 | Number of words. |
| ''$(**wildcard** pattern...)''           | Find file names matching a shell file name pattern (not a `%' pattern). |
| ''$(**error** text...)''                 | When this function is evaluated, make generates a fatal error with the message text. |
| ''$(**warning** text...)''               | When this function is evaluated, make generates a warning with the message text. |
| ''$(**shell** command)''                 | Execute a shell command and return its output. |
| ''$(**origin** variable)''               | Return a string describing how the make variable variable was defined. |
| ''$(**foreach** var,words,text)''        | Evaluate text with var bound to each word in words, and concatenate the results. |
| ''$(**call** var,param,...)''            | Evaluate the variable var replacing any references to ''$(1)'', ''$(2)'' with the first, second, etc. param values. |
... da fehlen welche