Problems with std::chrono

Question

I am having trouble compiling with chrono, here is the code:

Time.hh

#include        <chrono>

class           Time
{
protected:
  std::chrono::steady_clock::time_point _start_t;
  std::chrono::steady_clock::time_point _now;
  std::chrono::steady_clock::time_point _time;
public:
  Time();
  Time(const Time &other);
  Time          &operator=(const Time &other);
  ~Time();
public:
  void          start();
  double        getDurSec();
  double        getDurMilSec();
private:
  void          setNow();
};

Compilation error:

g++  -W -Wall -Wextra -I./include -std=c++0x  -c -o src/Time/Time.o src/Time/Time.cpp
In file included from src/Time/Time.cpp:11:0:
./include/Time/Time.hh:21:3: error: ‘steady_clock’ in namespace ‘std::chrono’ does not     name a type
./include/Time/Time.hh:22:3: error: ‘steady_clock’ in namespace ‘std::chrono’ does not name a type
./include/Time/Time.hh:23:3: error: ‘steady_clock’ in namespace ‘std::chrono’ does not name a type
src/Time/Time.cpp: In member function ‘void Time::start()’:
src/Time/Time.cpp:34:2: error: ‘_time’ was not declared in this scope
src/Time/Time.cpp:34:23: error: ‘std::chrono::steady_clock’ has not been declared

Etc...

Tell me if you need more informations.

Answer 1

You are probably using a g++ version prior to 4.7.0 where std::chrono::steady_clock was not implemented. If this is the case, you have two solutions:

• Upgrade your g++ to 4.7.0 or a more recent version.
• Use instead the old std::chrono::monotonic_clock.