英文:
How to specify the CFLAGS parameter in go build command line instead of in the go source file？
问题
例如，在go文件中的MY_NUM：
//#cgo CFLAGS: -DMY_NUM=3
/*
int multiple(int x) {
return x * MY_NUM;
}
*/
import "C"
....
但是我经常会更改MY_NUM的值。所以我想在构建命令中更改它。
我该如何在go build命令行中定义它？
英文:
For example, the MY_NUM in go file:
//#cgo CFLAGS: -DMY_NUM=3
/*
int multiple(int x) {
return x * MY_NUM;
}
*/
import "C"
....
But I will often change the value of MY_NUM. So I want change it in build command.
How can I define it in go build command line?
答案1
得分: 1
这不完全是一个go build选项，但你可以使用CGO_CFLAGS环境变量，例如：
$ cat foo.go
package main
/*
int multiple(int x) {
return x * MY_NUM;
}
*/
import "C"
import "fmt"
func main() {
fmt.Println(C.multiple(2))
}
$ CGO_CFLAGS="-DMY_NUM=10" go build foo.go
$ ./foo
20
$
来源：https://pkg.go.dev/cmd/cgo
在构建时，
CGO_CFLAGS、CGO_CPPFLAGS、CGO_CXXFLAGS、CGO_FFLAGS和CGO_LDFLAGS环境变量会添加到从这些指令派生的标志中。应该使用指令设置特定于包的标志，而不是使用环境变量，以便在未修改的环境中进行构建。从环境变量获取的标志不受上述安全限制的影响。
英文:
it's not exactly a go build option, but you could use the CGO_CFLAGS environment variable, e.g.:
$ cat foo.go
package main
/*
int multiple(int x) {
return x * MY_NUM;
}
*/
import "C"
import "fmt"
func main() {
fmt.Println(C.multiple(2))
}
$ CGO_CFLAGS="-DMY_NUM=10" go build foo.go
$ ./foo
20
$
from https://pkg.go.dev/cmd/cgo
> When building, the CGO_CFLAGS, CGO_CPPFLAGS, CGO_CXXFLAGS, CGO_FFLAGS
> and CGO_LDFLAGS environment variables are added to the flags derived
> from these directives. Package-specific flags should be set using the
> directives, not the environment variables, so that builds work in
> unmodified environments. Flags obtained from environment variables are
> not subject to the security limitations described above.
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论