Compilation of a macro with -std=c++11 flag

ROOT
1

Hello,

I am trying to run a macro which compiles some other macros in ROOT (Version 5.34), and some of the header files need C++ 11. I run a script which looks like this:

#!/bin/bash

COMPILE_LOGON=“~/analysis_master/customize_root/compile_logon.C”

root.exe -n $COMPILE_LOGON <<EOF
.L detector.hh++
.q
EOF

Where compile_logon.C is a ROOT macro which looks like this:

{
#include “string”
string ANAHOME=“~/”;
string tmp;

tmp = ANAHOME; tmp += “analysis_master/lib/lib64/root”;
char* inc = gSystem->ExpandPathName(tmp.c_str());
gInterpreter->AddIncludePath(inc);
delete inc;

gSystem->SetMakeSharedLib("g++ -std=c++11 -c $Opt -I. -I/user/sweeper/develop/unpacker/library/inc -fPIC $IncludePath $SourceFiles ; g++ $ObjectFiles -shared -L/user/sweeper/develop/unpacker/library/src -lSweeperUnpacker -Wl,-rpath=/user/sweeper/develop/unpacker/library/src -Wl,-soname,$LibName.so -m64 -O2 $LinkedLibs -o $SharedLib");

tmp = ANAHOME; tmp += “analysis_master/include”;
char* inc = gSystem->ExpandPathName(tmp.c_str());
gInterpreter->AddIncludePath(inc);
delete inc;
tmp = ANAHOME; tmp += “analysis_master/customize_root”;
char* inc = gSystem->ExpandPathName(tmp.c_str());
char* inc = gSystem->ExpandPathName(“~/analysis_master/customize_root”);
gInterpreter->AddIncludePath(inc);
gInterpreter->AddIncludePath(“/user/sweeper/develop/unpacker/library/inc”);
gSystem->SetFlagsDebug(“-std=c++11”);
gSystem->AddLinkedLibs(“-std=c++11”);
gSystem->SetFlagsOpt(“-std=c++11”);
delete inc;
}

As you can see, we have tried various ways to get the compiler to recognize the “-std=c++11” flag. But when I run it, I get an error which looks like this:

/usr/include/c++/4.9/bits/c++0x_warning.h:32:2: error: #error This file requires compiler and library support for the ISO C++ 2011 standard. This support is currently experimental, and must be enabled with the -std=c++11 or -std=gnu++11 compiler options.
#error This file requires compiler and library support for the
^
Error: external preprocessing failed. :0:
!!!Removing /user/e15091/analysis_master/src/sweeper_cc_ACLiC_dict.cxx /user/e15091/analysis_master/src/sweeper_cc_ACLiC_dict.h !!!
Error: /mnt/misc/sw/x86_64/Debian/8/root/gnu/5.34.32/bin/rootcint: error loading headers…
Error in : Dictionary generation failed!
Info in : Invoking compiler to check macro’s validity
Info in : The compiler has not found any problem with your macro.
Probably your macro uses something rootcint can’t parse.
Check http://root.cern.ch/viewvc/branches/v5-34-00-patches/cint/doc/limitati.txt for Cint’s limitations.

So despite all of our attempts, it seems like the compiler still doesn’t recognize the C++ 11 flag, and the compilation is failing.

Is there something I can do to get rid of this error?

Thank you.

2

You will probably have to move to ROOT 6 if you need C++11. The old CINT interpreter lacks support for a variety of C++ features and that was the main reason it was replaced with cling in ROOT 6.

3

Hello,

I was able to get it to compile properly on ROOT 6.06/02, but now when I run my compiled code I am getting this error:

cling::DynamicLibraryManager::loadLibrary(): libCint.so.5: cannot open shared object file: No such file or directory

I don’t know why it would be looking for a CINT shared object file, shouldn’t it be CLING? Any idea what could be causing this?

Thank you.

4

Did you pass -lCint during compilation? How did you compile your program?

5

I don’t pass -lCint anywhere that I am aware of. To compile I just ran the script above, except now in ROOT 6 instead of ROOT 5.

Doesn’t this line:

gSystem->SetMakeSharedLib("g++ -std=c++11-c $Opt -I. -I/user/sweeper/develop/unpacker/library/inc -fPIC $IncludePath $SourceFiles ; g++ $ObjectFiles -shared -L/user/sweeper/develop/unpacker/library/src -lSweeperUnpacker -Wl,-rpath=/user/sweeper/develop/unpacker/library/src -Wl,-soname,$LibName.so -m64 -O2 $LinkedLibs -o $SharedLib");

contain all the flags that I am passing to the compiler?

I also commented out these:

//gSystem->SetFlagsDebug("-std=c++11");
//gSystem->AddLinkedLibs("-std=c++11");
//gSystem->SetFlagsOpt("-std=c++11");

because they didn’t seem to be necessary.

6

Do you have the same problem if you compile from the command line? Something needs to be pointing to ROOT5 still for you to end up with a binary that requires libCint rather than libCling.

7

I realized now that the error

cling::DynamicLibraryManager::loadLibrary(): libCint.so.5: cannot open shared object file: No such file or directory

comes up whenever I open ROOT. So it’s not caused by me compiling/running my program. I think there is a path somewhere which is still pointing to something related to ROOT 5 instead of ROOT 6 for some reason.

Thanks for the help.

8

Hi,

as Guilherme says, you need to use ROOT6 to take advantage of new C++ stadards.
The error here points indeed to a faulty installation of ROOT. I would remove entirely ROOT5 from the system and start from scratch with ROOT6.

Cheers,
D

9

I found a path which was accidentally left pointing to a ROOT logon macro pointing to the ROOT 5 installation. Once I fixed that, the problems went away. My original code compiles and runs properly in ROOT 6.

Thanks.