未定义的引用`typeinfo for class' [英] undefined reference to `typeinfo for class'
本文介绍了未定义的引用`typeinfo for class'的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
可能重复:
g ++未定义对typeinfo的引用
未定义符号vtable for…”和" typeinfo for…&rdquo ;?
我无法使用类。
class Accel {
public:
virtual void initialize(void);
virtual void measure(void);
virtual void calibrate(void);
virtual const int getFlightData(byte);
};
class Accel_ad : public Accel {
public:
Accel_ad() : Accel(){}
void initialize(void) {/*code code code...*/}
void measure(void) {/*measure code*/}
const int getFlightData(byte axis){/*getting data*/}
void calibrate(void) {
int findZero[FINDZERO];
int dataAddress;
uint8_t data[2];
for (byte calAxis = XAXIS; calAxis < ZAXIS; calAxis++) {
if (calAxis == YAXIS) dataAddress = 0x32;
if (calAxis == XAXIS) dataAddress = 0x34;
if (calAxis == ZAXIS) dataAddress = 0x36;
for (byte i=0; i<FINDZERO; i++) {
readReverseWordI2C(dataAddress,data);
findZero[i] = (data[1] << 8) | (data[0]);;
Delay_ms(10);
}
accelZero[calAxis] = findMedian(findZero, FINDZERO);
}
// replace with estimated Z axis 0g value
accelZero[ZAXIS] = (accelZero[XAXIS] + accelZero[PITCH]) / 2;
// store accel value that represents 1g
measure();
accelOneG = -accelData[ZAXIS];
}
main.cpp
Accel_ad accel;//all ok
accel.initialize();//all ok
accel.calibrate();//ERROR: undefined reference to `typeinfo for Accel'
accel.measure();//All okey
谁知道错误?
推荐答案
您必须为基类中的虚拟函数提供定义或声明为pure:
You must either provide a definition for virtual functions in your base class or declare them pure:
class Accel {
public:
virtual void initialize(void) = 0; //either pure virtual
virtual void measure(void) = 0;
virtual void calibrate(void) {}; //or implementation
virtual const int getFlightData(byte) {};
};
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