#ifdef __cplusplus
extern "C" {
#endif
__declspec(dllexport) char* testing1(char* input);
__declspec(dllexport) char* testing2(char* input);

#ifdef __cplusplus
}
#endif

check.cpp
#include <cstdio>
#include <cstdlib>
#include <iostream>
#define DllExport __declspec(dllexport)

extern "C" __declspec(dllexport) char* testing1(char* input){
    return input;
}
extern "C" __declspec(dllexport) char* testing2(char* input){
    return input;
}

int main(int argc, char* argv[])
{
    char* result = testing1("testing ");
    std::cout<<"Result : "<< result<<std::endl;
}

package main
/*
#cgo LDFLAGS: -lCheck
#include <check.h>
#include <stdlib.h>
#include <string.h>
*/
import "C"
import "fmt"

//export AddTwoNums
func AddTwoNums(numone int, numtwo int) int {
    return numone + numtwo
}

//export Validate
func Validate(args *C.char) *C.char {
    str := C.GoString(args)
    str = str + "-" + str
    return C.CString(str)
}

func importFromClib1() {
    str1 := "Testing1"
    cstr := C.CString(str1)
    result := C.testing1(cstr)
    fmt.Println("Testing1 result : ", C.GoString(result))
}

func importFromClib2() {
    str1 := "Testing2"
    cstr := C.CString(str1)
    result := C.testing2(cstr)
    fmt.Println("Testing2 result : ", C.GoString(result))
}

func main() {
}