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Visit Stack Exchange I have a Makefile that has a variable that needs to have a default value in case when variable is unset or if set but has null value. I need this, as I invoke make inside a shell script and the value required by the makefile can be passed from the shell as $1.
If these were single colons, an warning would be printed and only the second set of commands would run.
4.12 Example requires: blah.c Generating prereqs automatically This makes one small makefile per source file Notes: 1) , with escaping.
Other macro languages you may be familiar with are the C preprocessor, allows you to define a shorthand term for a longer sequence of characters and use the shorthand in your program.
The macro processor will recognize your shorthand terms and replace them with their expanded form.
# Adding PHONY to a target will prevent make from confusing the phony target with a file name.
# In this example, if clean is created, make clean will still be run.
By list I mean a space seperated sentence of words.
variables for a while now and we’ve seen many examples of how they’re used in both the built-in and user-defined rules.
Comments Makefile Variable Assignment
Makefile cheatsheet - Devhints
The one-page guide to Makefile usage, examples, links, snippets, and more. #Var assignment. uglify = $uglify # lazy assignment compressor = $uglify # immediate assignment prefix ?= /usr/local # safe. #Magic variables. out.o src.c.…
Makefile Variables - adamcod.es
Before I did that, I felt I needed to give some background on the various types of variables and assignment available in Make for some of the.…
Variables in makefiles - Aggregate. Org
Variables in a makefile work much the same as variables in a shell script. The variable is assigned a string value via an assignment statement, such as…
What is the difference between the GNU Makefile variable.
Using ?= assigns the variable a value iff the variable was not. would result, which would most likely end the execution of your Makefile.…
Bash - Makefile Default Value of Variable that is set but has.
To set a value. make or make FOO= will end up setting FOO to bar ; you need override to override variables set on the command-line.…
Deferred Simple Variable Expansion GNU make
If these are true in your makefile, you're done. First, we can see that we're using a recursive variable assignment, so we know that the.…
Makefile Tutorial by Example
Makefile Tutorial by Example. This makefile will always run. files = file1 file2 some_binary $files echo "Look at this variable " $files touch some_binary file1 touch file1 file2 touch. You can assign variables for specific target patterns.…
GNU make Setting
To set a variable from the makefile, write a line starting with the variable name followed by ' = ', ' = ', or ' = '. Whatever. The shell assignment operator ' !=…