Makefile Ifdef Or, PHONY: deploy hello deploy: rsync . contro
Makefile Ifdef Or, PHONY: deploy hello deploy: rsync . controlled text will be included in the output of the preprocessor if and only if MACRO is defined. 深入讲解Makefile条件判断语句 (ifeq/ifdef)的用法，并剖析其仅在预处理阶段生效的核心原理，辅以语法对比、示例和5大注意事项，助您编写出更健壮、可预测的构建脚本。 A Makefile deploy recipe needs an environment variable ENV to be set to properly execute itself, whereas other recipes don't care, e. As this example illustrates, conditionals work at the textual level: the lines of the conditional are treated as part of the makefile, or ignored, according to the condition. I've got two different conditional statements. 6k次，点赞2次，收藏17次。文章详细介绍了Makefile中的条件判断语句ifeq,ifneq,ifdef,ifndef的使用方法及示例，以及如何定义命令包以简化代码。此外，还阐述了伪目标的 Conditionals affect which lines of the makefile make uses. 这个我就不多说了，和 ifdef 是相反的意思。 在 <conditional-directive> 这一行上，多余的空格是被允许的，但是不能以 Tab 键作为开始（不然就被认为是命令）。而注释符 # 同样也是安全的。 else 和 Instead, text is expanded and the resulting message is displayed, but processing of the makefile continues. 10 Variables from the Environment Variables in make can come from the environment in which make is run. It Conditionals affect which lines of the makefile make uses. It is basically a script that guides the make utility to choose the appropriate program files check: # make target ifndef APP_NAME # makefile conditional syntax echo "Empty" # recipe if condition true else # makefile conditional syntax echo "Not empty" # recipe if condition false endif # makefile Note that a variable set to an empty value is still defined, so ‘?= ’ will not set that variable. PHONY: SPOneDot SPOneDot: ifndef X X=0. Conditional Parts of Makefiles A conditional directive causes part of a makefile to be obeyed or ignored depending on the values of variables. $% The target member name, when the target is an archive member. Makefile Tutorial by Example Makefile Syntax A Makefile consists of a set of rules. Is it possible Makefile. The if function provides support for conditional expansion in a functional context (as opposed to the GNU make makefile conditionals such as ifeq (see Syntax of Conditionals)). override variable-assignment Define a variable, overriding any previous definition, even one from the command line. Use ifdef / ifndef to verify if variables exist, or ifeq / ifneq to compare their values. There are The ifeq Directive Checks if two values are equal. Conditionals can compare the value of one variable to another, or the value of a In this blog, we’ll demystify `if else` statements in Makefiles, explain why the "Unexpected End of File" error happens, and provide a step-by-step guide to writing robust The lines of the makefile following the ifneq are obeyed if the two arguments do not match; otherwise they are ignored. We commonly use this pattern in Makefiles to provide I capture the intent of the Makefile in pseudo code, then indicate the issues I have. If the condition is true, make reads the lines of the text-if-true as part of the makefile; if the condition is false, make ignores those lines completely. Tried hard, but can't find it. Conditionals affect which lines of the makefile make uses. A rule generally looks like this: targets: prerequisites command command I have a GNU Makefile (version 3. NMAKE searches for filename first in the specified or current directory, then recursively through directories of any parent makefiles, Prior to asking I had saw this, tried but didn't help : conditional compliation based on variable into makefile In my case my src_file. The current nested structure isn't really a nest - it is a series of if statements: There isn't any use o Makefileの条件分岐部分 条件分岐 (conditional)を使えば変数の値によってmakefileの一部を従うか無視するか分岐させることができます。条件分岐ではある変数を別の変数と比較するか、変数を定数文 How to use a variable from a Makefile in #ifdef in C++ file Asked 10 years, 8 months ago Modified 3 years, 5 months ago Viewed 7k times Conditionals affect which lines of the makefile make uses. But from there, you cannot set a Environment (GNU make) 6. Let me explain: I want to be able to specify a verbose compilation The ifdef form takes the name of a variable as its argument, not a reference to a variable. Conditional statements are supported in makefiles and can only be used to control statements actually executed by make. This 文章浏览阅读3. , ENV = . This I want to have multiple if condition and want to combine. However, you cannot control the 学习笔记：Makefile的ifeq逻辑或，逻辑与的变通实现 In my Makefile I would like to check the following complex condition: ifdef VAR1 || VAR2 || VAR3 action endif however the documentation says the syntax like that is not supported. If the value of that variable has a non-empty value, the text-if-true is effective; otherwise, the text-if It's common in makefiles to put all the . g. If the value of that variable has a non-empty value, the text-if-true is effective; otherwise, the text-if In Linux, Makefiles are powerful tools for automating build processes, but their syntax can sometimes be tricky, especially when it A conditional directive causes part of a makefile to be obeyed or ignored depending on the values of variables. 81) that looks like the following: . $< The name of the first prerequisite. 조건은 make 가 실제로 Unconditional makefile text follows. $(ENV). CC = gcc endif In this case, if the CC variable isn’t defined, the Makefile assigns “gcc” as its default value. However, every conditional check within my function se 使用条件判断，可以让make在编译程序时，根据不同的情况，执行不同的分支：可以执行不同的命令，使用不同的编译参数，生成不同的目标。在 Makefile 中， Makefile has four conditional statements: ifeq (two values are equal), ifneq (two values are not equal), ifdef (value is defined), and ifndef (value is not defined). It 文章浏览阅读7. Every environment variable that make sees when it starts up is A makefile here has nested if statements to assign variable values and targets to be built. I'm trying to setup a Makefile that will search and copy some files (if-else condition) and I can't figure out what exactly is wrong with it? (thou I'm pretty sure it's Makepp Statements Various statements in a makefile Conditionals Other Multiline Statements Simple Statements Commands A: autoload, B: build_cache, build_check, D: define, E: export, G: global, I: Reads filename as a makefile, then continues with the current makefile. , a directory with a name i386, or sparc, or something that depends on the machine type). It follows that syntactic units of the makefile, such as In C++ development, conditional compilation is a powerful technique to control which parts of your code are compiled—whether for debugging, enabling optional features, or handling platform-specific logic. I'd like to enable a verbose compilation in my makefile, but I can't figure out how to make a conditional OR. The result of the expansion of this function is the empty string. Conditionals can compare the 0 0 升级成为会员 « 上一篇： makefile笔记5 - makefile变量 » 下一篇： makefile笔记7 - makefile函数 发表于 2018-09-05 23:11 不游泳的鱼 阅读 (2885) 评论 (0) 收藏 举报 刷新页面 返回顶部 登录后才能查 文章浏览阅读3. I'm looking for a Makefile which is more user friendly in a test environment. #endif It did not work? What is the proper way? Makefiles, ifdef and computed variables Asked 4 years, 10 months ago Modified 1 year, 5 months ago Viewed 407 times I have a Makefile with 2 ifdef conditions that perform same action when that particular config is selected. A conditional directive causes part of a makefile to be obeyed or ignored depending on the values of variables. One checks for the existence of the $(MAKECMDGOALS) special va I have the following makefile for my project, and I'd like to configure it for release and debug builds. 05 $$(info X undefined, changed to $X) endif ifndef Y Y=0. exa If function in Makefile seems to disregard conditional and executes unexpectedly Ask Question Asked 4 years, 10 months ago Modified 4 years, 10 months ago You can arrange to compile the same source file into two different programs by choosing a macro name to specify which program you want, writing conditionals to test whether or how this macro is defined, Structure of else and endif Conditional blocks in Makefiles use else to define alternative logic when the initial condition fails, and endif to terminate the block. So the only simple Conditionals affect which lines of the makefile make uses. This ensures builds adapt to user-specific configurations If the condition is true, make reads the lines of the text-if-true as part of the makefile; if the condition is false, make ignores those lines completely. A frequently-used target is 'make clean', which removes any temporary files, or 'make install', which installs the What is a Makefile? A Makefile is used with the make utility to determine which portions of a program to compile. Conditional directives in Makefiles enable environment checks. The correct usage of the Makefile 1. You are testing an environment variable in a shell command executed by make. $? The names of all the prerequisites that are newer than the Unconditional makefile text follows. DATE: 2019-2-22前言 条件分支的用法在任何编程语言和脚本以及逻辑中都广泛使用。 前文讲述过C语言中预处理的条件编译#ifdef/#if/#elif/#else/#endif用法详解，本文重点讲述Makefile编译脚本中条件分 I've written a fairly simple test Makefile where I define two targets, all & clean. I have tried this one, but failed. These directives follow the syntax: makefile The controlled text inside of a conditional can include preprocessing directives. Any help is appreciated. You can nest conditional groups inside other conditional groups, but they Conditional Parts of Makefiles A conditional causes part of a makefile to be obeyed or ignored depending on the values of variables. c contains: #ifndef WITH_ATS #define WITH_ATS #include "ats. ? I tried: #ifdef LINUX | ANDROID . They are executed only if the conditional succeeds. 5k次，点赞11次，收藏13次。 本文详细介绍了Makefile中的条件判断语句ifeq,ifneq,ifdef,ifndef的用法，以及如何进行多条件判断、循环（foreach与shell脚本）、自定义函数 ifneq ($(farm_batch),0) \ echo "please input the correct value" \ endif \ endif \ target: #do something here using $(farm_batch) Note: When I remove the backlashes, I encountered additional errors which are: else 和 endif 也一样，只要不是以 Tab 键开始就行了。 特别注意的是，make是在读取Makefile时就计算条件表达式的值，并根据条件表达式的值来选择语句，所以，你最好不要把自动化变量（如 $@ “else”和“endif”也一样，只要不是以 [Tab]键开始就行了。 特别注意的是，make是在读取Makefile时就计算条件表达式的值，并根据条件表达式的值来选择语句，所以，你最好不要把自动化变量（如“$@” Making Compiling Easier: Makefiles and #ifndef When programs use several different classes, each in its own header and definition file, two features of C++ (and C) help us manage the files. Makefile 条件判断作用条件语句可以根据一个变量的值来控制 make 执行或者时忽略 Makefile 的特定部分，条件语句可以是两个不同的变量或者是常量和 As the conditional-directive ifeq is frequently used to compare word(s) expanded from variables, which often contains white-space, we may want and, in fact need, for Make to strip any leading or tr so here in my Makefile I could indend the ifeq with spaces only? , In the later content of that Makefile, I have indented with tabs also, is that a problem? and why not, if not? maybe you can start a PR on 조건 (conditional) 은 makefile의 어떤 부분이 변수의 값에 따라서 사용되거나 무시되도록 한다. In my code, I have lots of #ifdef DEBUG macros in place, so it's simply a matter of setting I am trying to write a make function to touch/create an empty file and/or set the permissions, user and group, where possible, or warn if not. I have a Makefile target, in which I have to check the value of an environment variable. Syntax: ifeq (ARG1, ARG2) or ifeq "ARG1" "ARG2". Makefile (2) Learn to customize your software build process using Makefile flavors and conditional logic for efficient management of complex projects with multiple files Conditionals affect which lines of the makefile make uses. It Makefile Tutorial by Example Makefile Syntax A Makefile consists of a set of rules. 9w次，点赞27次，收藏105次。1. A rule generally looks like this: targets: prerequisites command command Unconditional makefile text follows. Learn the basics of using variables in a Makefile, followed by using the ?= operator for a more advanced use case $ export myvar=notDefault $ make echo notDefault notDefault And in case the environment variable and the make variable are the same - and why not? - it is simpler still. The ifdef directive begins the conditional, and specifies the condition. ifeq ($(TAG1), on) LD_FLAGS += -ltestlibrary endif ifeq ($(TAG2), on) LD_FLAGS += -ltestlibrary endif I want to do some thing like: ifeq Makefile ifeq logical AND Asked 14 years, 7 months ago Modified 2 years, 2 months ago Viewed 66k times Can someone explain how to use if-then statements and for loops in Makefiles? I can't seem to find any good documentation with examples. Compares arguments after expanding variables. The make documentation says the syntax of a complex conditional is as follows: conditional-directive-one text-if-one-is-true else conditional-directive-two text-if-two-is-true else text-if-one-and- Include another makefile. o files in a subdirectory (e. It GNU Makeの「Conditionals（条件分岐）」ですね。これは、簡単に言うと「もし〇〇なら、この設定を使う。そうでなければ、こっちを使う」というルール In your comment you mention "contain recipes before the first target" which is a completely different kind of error, that cannot happen only with the example makefile you show above. . Conditionals can compare the value of one variable to another, or the value of a The ifdef form takes the name of a variable as its argument, not a reference to a variable. It Ifdef (The C Preprocessor) This block is called a conditional group. Conditionals can compare the value of one variable to another, Both #ifdef and #ifndef are useful, as justification consider this contrived example: you have a bunch of debug printf code that you only want to compile into a Debug build, using #ifdef DEBUG conditions. See Including Other Makefiles. Environment Makefiles are the backbone of build automation, enabling developers to define custom workflows for compiling code, running tests, or deploying applications with a single `make` command. See section Conditional Parts of Makefiles. This Makefile my_test: ifdef $(toto) @echo 'toto is defined' else @echo 'no toto around' endif Expected behavior $ make my_test no toto around $ make my_test toto Makefile ifeq、ifneq、ifdef和ifndef（条件判断） 日常使用 Makefile 编译文件时，可能会遇到需要分条件执行的情况，比如在一个工程文件中，可编译的源文件很多，但是它们的类型是不相同的，所以编译 A Makefile can offer several different "targets", which can be invoked by 'make <target>'. It ifndef with multiple AND conditions in makefile gnu Asked 2 years, 11 months ago Modified 2 years, 11 months ago Viewed 1k times 条件判断 条件判断在Makefile中常用于根据不同的情况执行不同的操作。 Makefile中的条件判断使用ifeq、ifneq、ifdef和ifndef等关键字来实现。 下面我们分别介绍 I would like to set OR condition in #ifdef directive. See The override Directive. $@ The file name of the target. But, I don't get the exact syntax of it. We say that the conditional succeeds if That's not an answer to the question how to set a Makefile variable if it isn't set. . 조건은 한 변수를 다른 것과, 또는 한 변수의 값을 상수 문자열과 비교할 수 있다. Conditionals can compare the value of one variable to another, or the value of a Conditionally evaluate part of the makefile. am doesn't support recursive if conditions. A conditional causes part of a makefile to be obeyed or ignored depending on the values of variables. 045xr, 8axr, 7061, 2xr8, 9gp5l, 1dkqr, nss0ox, qfavb, 5bwv, qyqz,