Question

我创建了一个C API，它公开了C ++代码的功能。这是opencv_test.h的代码：

#ifdef __cplusplus
#define EXTERNC extern "C"
#else
#define EXTERNC
#endif

EXTERNC void OpenVideo(char *filename);

#undef EXTERNC

opencv_test.cpp的代码：

#include <iostream>
#include <unistd.h>
#include "opencv_test.h"
#include "opencv2/opencv.hpp"

using namespace std;
using namespace cv;


void OpenVideo(char *filename){
    VideoCapture cap(filename);
    Mat Uframe;
    int frameCount = 0;

    if(!cap.isOpened()){
        cout<<"Cannot open video file!";
        return;
    }

    namedWindow("Video");
    while(++frameCount){

        bool success = cap.read(Uframe);

        if(!success){
            cout<<frameCount<<" frames read";
            break;      
        }

        imshow("Video", Uframe);
        waitKey(1);

    }

}

最后，对于opencvTest.go：

package main

/*
#cgo LDFLAGS: -L/usr/local/lib -lopencv_core -lopencv_video -lopencv_videoio -lopencv_highgui
#include <stdlib.h>
#include "opencv_test.h"
*/
import "C"

func main(){

    theFilename := "DRŽAVNI POSAO [HQ] - Ep.323 Dan žena (07.03.2014.).avi"
    C.OpenVideo(C.CString(theFilename))
}

我得到的错误如下：

命令行参数/tmp/go-build823465636/b001/_x002.o：在函数“ _cgo_dcf5d601f507_Cfunc_OpenVideo”： / tmp / go-build / cgo-gcc-prolog：48：未定义对“ OpenVideo”的引用 collect2：错误：ld返回1退出状态

现在，我不确定是否必须运行任何类型的特殊命令或其他命令，我已经读过，只要导入“ C” 伪软件包，我的.go文件就可以用cgo构建。因此，如果我包含了自定义的.h文件，并且该项目是使用cgo构建的，我怎么会得到未定义的对函数的引用错误？

编辑：

这是运行go build -x opencvTest.go命令时的全部输出：

WORK = / tmp / go-build568047770

mkdir -p $ WORK / b001 /

cd / home / stefan / Desktop / GoLang

CGO_LDFLAGS ='“-L / usr / local / lib”“ -lopencv_core”“ -lopencv_video”   “ -lopencv_videoio”“ -lopencv_highgui”“ -L / usr / local / lib”   “ -lopencv_core”“ -lopencv_video”“ -lopencv_videoio”   “ -lopencv_highgui”'/ usr / local / go / pkg / tool / linux_amd64 / cgo -objdir   $ WORK / b001 / -importpath命令行参数--I / usr / local / include   -I $ WORK / b001 / -g -O2 ./opencvTest.go

cd $ WORK

gcc -fno-caret-diagnostics -c -x c-||是

gcc -Qunused-arguments -c -x c-||是

gcc -fdebug-prefix-map = a = b -c -x c-||是

gcc -gno-record-gcc-switches -c -x c-||是

cd $ WORK / b001

TERM ='dumb'gcc -I / home / stefan / Desktop / GoLang -fPIC -m64 -pthread   -fmessage-length = 0 -fdebug-prefix-map = $ WORK / b001 = / tmp / go-build -gno-record-gcc-switchs

-I / usr / local / include -I ./ -g -O2 -o ./_x001.o -c _cgo_export.c TERM ='dumb'gcc -I / home / stefan / Desktop / GoLang -fPIC- m64 -pthread   -fmessage-length = 0 -fdebug-prefix-map = $ WORK / b001 = / tmp / go-build -gno-record-gcc-switchs

-I / usr / local / include -I ./ -g -O2 -o ./_x002.o -c opencvTest.cgo2.c TERM ='dumb'gcc -I / home / stefan / Desktop / GoLang- fPIC -m64 -pthread   -fmessage-length = 0 -fdebug-prefix-map = $ WORK / b001 = / tmp / go-build -gno-record-gcc-switchs

-I / usr / local / include -I ./ -g -O2 -o ./_cgo_main.o -c _cgo_main.c cd / home / stefan / Desktop / GoLang TERM ='dumb'gcc -I。 -fPIC -m64 -pthread   -fmessage-length = 0 -fdebug-prefix-map = $ WORK / b001 = / tmp / go-build -gno-record-gcc-switches -o $ WORK / b001 / cgo .o $ WORK / b001 / _cgo_main.o $ WORK / b001 / _x001.o $ WORK / b001 / _x002.o -L / usr / local / lib -lopencv_core   -lopencv_video -lopencv_videoio -lopencv_highgui -L / usr / local / lib -lopencv_core -lopencv_video -lopencv_videoio -lopencv_highgui

命令行参数/tmp/go-build568047770/b001/_x002.o：在   功能_cgo_dcf5d601f507_Cfunc_OpenVideo': /tmp/go-build/cgo-gcc-prolog:48: undefined reference to OpenVideo'   collect2：错误：ld返回1退出状态

在GoLang中运行OpenCV-4.0.0 C ++函数

0 个答案: