CGo不在同一目录中编译C文件

Question

我正在尝试使用同一目录中的单独C源文件创建一个CGO程序。如官方Cgo文档中所述，Cgo将在同一目录中编译所有C文件，但在这种情况下，它不会编译C文件。后来给出了链接器错误。

myTest.go

package main

/*

#include <stdlib.h>
#include "myTest.h"

*/
import "C"
import "unsafe"

func Print(s string) {
    cs := C.CString(s)
    C.print_str(cs)
    C.free(unsafe.Pointer(cs))
}

func main() {
    str1 := "hi how are you\n"
    Print(str1)
}

myTest.h

void print_str(char *s);

myTest.c

#include "stdio.h"

void print_str(char *s)
{
    printf("%s\n", s?s:"nil");
}

编译时，出现以下错误：

> go build myTest.go

# command-line-arguments
/tmp/go-build989557946/b001/_x002.o: In function `_cgo_4c80c9e4eaf0_Cfunc_print_str':
/tmp/go-build/cgo-gcc-prolog:49: undefined reference to `print_str'
collect2: error: ld returned 1 exit status

Go版本是：

> go version
go version go1.10 linux/amd64

Answer 1

$ go help build
usage: go build [-o output] [-i] [build flags] [packages]

Build compiles the packages named by the import paths,
along with their dependencies, but it does not install the results.

If the arguments to build are a list of .go files, build treats
them as a list of source files specifying a single package.

<< SNIP>>

如果要构建的参数是.go文件列表，则build会将其视为指定单个程序包的源文件列表。

> go build myTest.go

建立档案 myTest.go

跑

> go build