Unable to compile root programs outside root environment

[Debajyoti_Sengupta]

Please provide the following information:

---

ROOT Version (5.34.36):
Platform, compiler (Windows 10):

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(I am using root 5.34.36 (on windows 10)
I am unable to compile this code outside of root.
This is my code ( I save it as a .cpp file and try to execute it outside root using g++ (filename).cpp) and i get the error :

#include <iostream>
#include <TObject.h>
#include <TROOT.h>
#include<TFile.h>
#include <TTree.h>
using namespace std;
int main ()

{
cout << “Hellow World” << endl;
return 0;
}

C:\Users\DEBAJY~1\AppData\Local\Temp\ccgInqnq.o:rootpr.cpp:(.text+0x92): undefined reference to `TVersionCheck::TVersionCheck(int)’
collect2.exe: error: ld returned 1 exit status

[bellenot]

Hi,

@Debajyoti_Sengupta

This is my code ( I save it as a .cpp file and try to execute it outside root using g++ (filename).cpp) and i get the error :

Which version of ROOT do you use exactly? if it’s the native one, you have to compile with cl.exe, not g++
And see also Posting code? Read this first!

Cheers, Bertrand.

[sbinet]

also: how do you compile it? (i.e. please post the exact command line you use to compile this. it seems to me you may be missing mandatory linkopts)

[Debajyoti_Sengupta]

My filename is rootpr.cpp and i use

g++ rootpr.cpp -o rootpr.exe

[Debajyoti_Sengupta]

I am using root 5.34.36 on windows 10

[sbinet]

You’d need to wire in ‘root-config --cflags --libs’ into the compilation invocation.
(At least on Unix)

[Debajyoti_Sengupta]

So I compile with

g++ rootpr.C -o rootpr.exe ‘root-config --cflags --libs’

and I get the error :
g++: error: `root-config: No such file or directory
g++: error: unrecognized command line option ‘–cflags’
g++: error: unrecognized command line option ‘–libs’’

[sbinet]

Sorry, I am typing from my phone.
I am not a Windows expert and I don’t know if the backticks ` work like on Unix.
Run the root-config command I alluded to earlier and copy paste the result in your compilation invocation.

[Debajyoti_Sengupta]

I tried compiling using

g++ rootpr.C -o rootpr.exe `root-config --cflags --libs`

I get the same error