Intel C ++ error: "pair" is not a non-statistical data element or base class class "std :: pair <const int, double>"

Question

I am using the Intel C ++ compiler with qmake in QtCreator. In my project, I am using std :: map.

std::map<int,double> dataBase; dataBase[2] = 2.445; 

This code compiles and runs without problems using g ++. If I try to compile with ICC, the following error will occur:

 /usr/include/c++/4.8.0/tuple(1075): error: "pair" is not a nonstatic data member or base class of class "std::pair<const int, double>" 

The full compiler error is much longer. I got a little confused on the inclusion path, because for me it looks like the g ++ library that is used. If I comment on this section, the program compiles and I can verify that ICC has been used.

Does anyone know why the Intel C ++ compiler is causing this error?

Edit:

I create a minimal example and find a compiler option that causes this problem: Folowing is the contents of the * .pro file

 TEMPLATE = app CONFIG += console CONFIG -= app_bundle CONFIG -= qt SOURCES += main.cpp QMAKE_CXXFLAGS += -std=c++11 

main.cpp

 #include <iostream> #include <map> using namespace std; int main(){ map<int,double> dataBase; dataBase[2] = 2.445; cout << dataBase[2] << endl; return 0; } 

He works without

 -std=c++11 

but causes a compiler error.

Answer 1

I have the same problem as you describe ... really strange. Every other compiler (clang, gcc, msvc11) compiles it without any problems. I think this is because of the 4.8.x headers. icpc -v says at least version 13.1.1 (gcc version **4.7.0** compatibility) ...

Workaround:

 template<class K, class V> V &changemapvalue(std::map<K, V> &map, K &key, V &val) { #if defined(__GNUC__) && defined(__INTEL_COMPILER) if (map.find(key) != map.end()) map.erase(key); map.insert(std::pair<K, V>(key, val)); #else map[key] = val; #endif //__GNUC__ && __INTEL_COMPILER return val; } 

But this is stupid.

Answer 2

If you consider vector<char> , one element is represented as just a char .

A map however (and other associative containers) is not represented in this way. Rather, they are represented as a pair :

{C ++ 03} 23.3.1 / 2

 typedef pair<const Key, T> value_type; 

I am not familiar with the Intel C ++ compiler, but judging by the error message, I would say that Intel implements pair in terms of the tuple class. A tuple class is a collection of things. A pair , for example, will be a tuple with two elements.

All of the above is just a study and does not really say why you get this error. /usr/include/c++/4.8.0 looks like the include directory for g ++ 4.8.0 - the latest version of g ++. If the Intel compiler is looking here, I would say that your paths are corrupted, both in your environment and in the paths sent to the Intel compiler.

Check the environment variables and your file.

Answer 3

When it comes to C ++ 11, for some reason icpc doesn't like the [] std :: map operator.

To enter new values ​​you need to use the insert() method, and to access existing values ​​you can use the C ++ 11 at() method.

This compiles with icpc -std=c++11

 #include <iostream> #include <map> using namespace std; int main(){ map<int,double> dataBase; dataBase.insert(pair<int,double>(2,2.445)); cout << dataBase.at(2) << endl; return 0; }