打开g ++优化会导致段错误 - 我不明白

rob*_*ene 10 c++ optimization g++ segmentation-fault

我一直在研究我的程序,我决定使用它来开启一些优化g++ -O3.突然,我的程序开始了segfaulting.我已经找到了有问题的代码,并将我的程序最小化到仍然是段错误的东西(仅在使用3级优化时).我希望有人可以快速浏览代码(我尽可能地尽量减少它):

// src/main.cpp
#include "rt/lights/point.hpp"
int main(int argc, char **argv)
{
    rt::Light *light = new rt::light::Point(alg::vector(.0f, 5.0f, 5.0f), rt::Color(1.0f), .5f);
    return 0;
}


// include/rt/lights/point.hpp
#ifndef RT_LIGHT_POINT_HPP_
#define RT_LIGHT_POINT_HPP_

#include "rt/accelerator.hpp"
#include "rt/color.hpp"
#include "rt/intersection.hpp"
#include "rt/light.hpp" // abstract

namespace rt {
namespace light {

class Point : public Light
{
  public:
    Point(alg::vector pos, Color color, float intensity) : Light(intensity * color), pos(pos) {}

    Color get_contrib(const Intersection&, const Accelerator&, const alg::vector& toViewer) const;

  private:
    alg::vector pos;
};

} // namespace light
} // namespace rt

#endif


// include/rt/light.hpp
#ifndef RT_LIGHT_HPP_
#define RT_LIGHT_HPP_

#include "algebra/vector.hpp"
#include "rt/color.hpp"

namespace rt {

class Intersection;
class Accelerator;

class Light
{
  public:
    Light(Color intensity) : intensity(intensity) {}

    virtual Color get_contrib(const Intersection&, const Accelerator&, const alg::vector& toViewer) const = 0;

    Color get_intensity() const {return intensity;}

  protected:
    Color intensity;
};

} // namespace rt

#endif
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我希望能够深入了解为什么这段代码在使用优化时只会出现段错误,以及如何阻止它这样做.谢谢!

$ find src/ -name "*.cpp" | xargs g++ -I include/ -O3
$ ./a.out
Segmentation fault
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编辑:根据请求,alg :: vector的构造函数

struct vector
{
    float x, y, z;
    vector() : x(.0f), y(.0f), z(.0f) {}
    explicit vector(float f) : x(f), y(f), z(f) {}
    vector(float x, float y, float z) : x(x), y(y), z(z) {}
    // ...

Edit2:编译时添加gdb输出 -g

(gdb) file a.out
Reading symbols from /home/rob/devel/gbug/a.out...done.
(gdb) run
Starting program: /home/rob/devel/gbug/a.out 

Program received signal SIGSEGV, Segmentation fault.
rt::light::Point::Point (this=0x804b008, pos=..., color=..., intensity=0.5)
    at src/rt/lights/point.cpp:13
13  Point::Point(alg::vector pos, Color color, float intensity) : Light(intensity * color), pos(pos)
(gdb) bt
#0  rt::light::Point::Point (this=0x804b008, pos=..., color=..., intensity=0.5)
    at src/rt/lights/point.cpp:13
#1  0x08048898 in main (argc=1, argv=0xbffff3e4) at src/main.cpp:5

Edit3:rt :: Color的来源.

// include/rt/color.hpp
#ifndef RT_COLOR_HPP_
#define RT_COLOR_HPP_

#include "algebra/vector.hpp"

namespace rt {

/*******************************************************************************
 * CLASS DEFINITION
 */

struct Color
{
    float r, g, b;
    Color() : r(.0f), g(.0f), b(.0f) {}
    explicit Color(float f) : r(f), g(f), b(f) {}
    Color(float r, float g, float b) : r(r), g(g), b(b) {}

    Color& operator+= (const Color&);
    Color& operator*= (const Color&);
    Color& operator*= (float);
};

/*******************************************************************************
 * MEMBER OPERATORS
 */

inline Color& Color::operator+= (const Color& other)
{
    r += other.r;
    g += other.g;
    b += other.b;
    return *this;
}

inline Color& Color::operator*= (const Color& other)
{
    r *= other.r;
    g *= other.g;
    b *= other.b;
    return *this;
}

inline Color& Color::operator*= (float f)
{
    r *= f;
    g *= f;
    b *= f;
}

/*******************************************************************************
 * ADDITIONAL OPERATORS
 */

inline Color operator+ (Color lhs, const Color& rhs)
{
    return lhs += rhs;
}

inline Color operator* (Color lhs, const Color& rhs)
{
    return lhs *= rhs;
}

inline Color operator* (Color c, float f)
{
    return c *= f;
}

inline Color operator* (float f, Color c)
{
    return c *= f;
}

} // namespace rt

#endif

sth*_*sth 6

在计算时intensity * color,间接地调用此运算符:

inline Color& Color::operator*= (float f)
{
    r *= f;
    g *= f;
    b *= f;
}
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它声称返回对a的引用Color,但没有.它应该返回一个引用*this,就像其他运算符一样:

return *this;
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  • 啊.我想这里有一个值得学习的教训......总是使用-Wall. (3认同)
  • @James:如果您指定`-Wall`,则会启用该警告。 (2认同)
  • @James:还可以使用“-Werror”,这样您就不会偷懒,将警告“留到以后”。 (2认同)