$(wildcard $^) expands all the dependencies of the target, what does this $^ mean?
时间: 2024-01-16 10:04:26 浏览: 30
`$^` is a special variable in Makefile that represents all the dependencies of a target, separated by spaces.
For example, if you have the following rule:
```
main: file1.o file2.o
gcc -o main file1.o file2.o
```
`$^` will expand to `file1.o file2.o`.
`$(wildcard $^)` is a Makefile function that expands any wildcard characters in the string passed as argument. In this case, we're passing `$^` as argument, which is expanded to the list of dependencies of the target. Therefore, `$(wildcard $^)` expands all the dependencies of the target, and returns a list of files that match any wildcard characters in the dependencies.
For example, if you have the following dependencies with wildcard characters:
```
main: *.c
gcc -o main $(wildcard *.c)
```
`$^` will expand to `*.c`, and `$(wildcard $^)` will expand to a list of all the `.c` files in the current directory.