The problem occurs when trying to use CDT for editing files in OpenFOAM, a popular computational fluid dynamics software package. I am using Eclipse Kepler SR2 Build id: 20140224-0627 and CDT 8.3.0.201402142303 The following is a simplified version of the problem.
Given the following hello.cpp
#include <iostream>
#include <string>
int main(){
#include "hello.H"
std::cout << hello << std::endl;
}
and the following hello.H
std::string hello("Hello world!");
Indexing can't resolve hello in hello.cpp. However, if I change hello.H to hello.inc it does work. This isn't a feasible solution for OpenFOAM. How could I make the indexing and autocomplete work with the given structure?
Note: I did try Eclipse Luna too, and the same happened.
Edit: I think this might be a bug. After more experimenting, the following happened. When I named the hello.H to hello.inc, the hello in hello.cpp was recognized. However, when I rebuild index it wasn't. Then I resaved hello.inc without functional changes, and behold, it was recognized again. However, if I turned off automatic indexing it no longer got resolved after rebuilding the index.
Edit 2: After further research on the problem, I found the following duplicates, without the random behavior:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=418085
and to my shame:
#include inside function body doesn't work (CDT/Eclipse C++)
Thus this question can be closed as a duplicate. To those interested, CDT indexer is not actually designed to do this, as this is bad coding style. The main message to me was that I should use some other IDE with OpenFoam.
Related
I'm currently working on a class assignment that requires the use of the CImg library. To be clear, the assignment is not linking the library into the program; The class is using it access the pixel data for later use in the heart of the assignment.
I'm working in Xcode (OS X 10.10). CImg (2.2.2) is installed from homebrew, and I've managed to navigate the weird way Xcode deals with search paths (added the header to the section), and have successfully-ish included CImg.
my full code is as below.
#include <iostream>
#define cimg_display 0 //I don't need X11 at all
#include "CImg.h"
using namespace cimg_library;
int main(int argc, const char * argv[]) {
// insert code here...
std::cout << "Hello, World!\n";
return 0;
}
However, I get 17 Compile-time errors from CImg.h, which are very unusual, and all of the form:
"No member named 't_normal' in the global namespace; did you mean simply 't_normal'?"
Thinking I might have received a bad download, I have attempted to redownload CImg, with no luck. I have also gotten to this same point with non-homebrew versions of CImg.
To verify the download, I also compiled the examples from the command line and they ran perfectly.
Is there a problem with CImg that I'm not aware of, a problem with Xcode that I'm not aware of, or is there something fundamental that I'm missing (definitely an option, my C-style programming is a little rusty) ?
halp pls.
Your code runs fine if you do this:
Create a new Xcode project, with:
type = "Command Line Tool"
language = "C++"
Then go to "Build Settings" and add the path to the directory containing CImg.h to your "User Header Search Paths"
I have 2 program I wrote on my windows computer using Visual Studio 2013. They run fine and work perfectly on my computer, but when I brought them over to my school account that is on a Linux machine, a problem arose. They compile and 1 ran, but the other did not. The one that did not run gave me an error:
.../lib/compat/libstdc++.so.6: version CXXABI_1.3.2 required by...
I have been doing research and I can't seem to find out what in my program would be using libstdc++.so.6, I'm not even really sure what it is or does. Since I am on a student account I can't go installing it using sudo, and it is a homework so I can't submit it using my own libraries.
Any Idea on what my program might be using that would require libstdc++.so.6?
I have 3 files: main.cpp, LinkedList.cpp and LinkedList.h.
I think it might be in main.cpp because I think it stems from a library I am including and main.cpp is the only one that uses outside libraries. Here is the list of libraries it uses:
#include <iomanip>
#include <stdio.h>
#include <fstream>
#include <ctype.h>
#include <string>
#include <iostream>
#include <vector>
#include <sstream>
#include <bitset>
#include <algorithm>
#include "LinkedList.h"
Thanks in advance!
You are trying to run a program linked against one version of the libraries under another set. That should work fine as long as the library versions aren't too far apart. In your case, the difference between libraries is just too large.
GCC (C++ in particular) has changed quite a bit lately, some programs that used to compile and run fine now blow up or don't compile at all (due to language changes, compiler bugs accepting broken code, ...), and the library ABI has also changed. Your best bet is to carry source code around, and make sure you got compatible language versions on both ends. If that is inconvenient, a solution is to make sure you have the same compiler (and other environment) at both places. The easiest way to get this is to install the same distribution and version.
First you can't remove the dependencies of libstdc++.so.6, because it's a standard C++ library.
To solve your problem you have to check whether your libstdc++.so have the right version
strings /usr/lib64/libstdc++.so.6|grep GXXABI_1.3.1
if there have no matching version, you will have 2 methods like these:
update your gcc on your school's linux OS
yum intsall gcc
download a matching libstdc++.so from this website:
download gcc || download matching libstdc++
then replace the libstdc++.so to /usr/lib64/libstdc++.so.6.*
SOLUTION
I went through a few steps to find my solution. Originally I could compile my program but could not run it.
1) My first step to solve the issue was to change my method of compiling. Originally I compiled my program with the following: g++ main.cpp LinkedList.cpp -o output. I changed it to: g++ -static main.cpp LinkedList.cpp -o output which allowed me to compile and run. This worked but static is a method to dynamically link libraries. This prevents linking with the shared libraries. This is not a good solution because it takes a lot longer and increases the file size of the executable, so I wanted to improve.
2) The second thing I did was remove using namespace std. Yes, I cheated and used it. So I went through my program and added std:: to the appropriate places.
3) The last thing I did was clean up my code. I was using a lot of libraries because my program was a large and complicated program. I was using all of the libraries I had listed in my original post. I went through my code and anywhere I was using a function from a library I would try and write my own code that would do the same thing which would result in my program not depending on those libraries. I was able to replicate a decent amount of these dependent foreign functions with my own which added lot of code, but it allowing me to remove some of these includes. My list of includes is now:
#include <fstream>
#include <string>
#include <iostream>
#include <vector>
#include <algorithm>
#include "LinkedList.h"
#include <math.h>
I am not sure exactly which step resolved my issue, but now I can compile with my preferred method, g++ main.cpp LinkedList.cpp -o output, and my program runs fine.
I hope this helps someone.
I have this piece of code :
#include <iostream>
#include <type_traits>
using namespace std;
int main(){
cout << std::is_same<int,int>::value; // this line is underlined (as a error)
return 0;
}
I am not quite used to code C++ in Eclipse.
So I have a Eclipse luna-SR2-32 (latest version), and I use tdm-gcc-4.9.2 as a compiler.
So the issue is that Eclipse underlines that line (look at the code) (is_same and value couldn't be resolved), however he has no problem including type_traits, I can even open it from eclipse Editor, and see that 'is_same' is the file.
When I compile and run it, it works fine but it stills underlined which is bothering me... It doesn't do this with some other c++11 features as tuple ...
I know this needs probably a simple configuration in Eclipse, but I tried many things already ... I added -std=c++11 in the compiler options (but nothing changed).
EDIT :
I tried the 3 first answers of this, but none of them worked ...
But I tried using instead and now it is not underlined anymore ... Why is that ? I know that some librairies are in tr1 because they were added later, but why does he recognize and can run it, but still underlines my lines when I use it ?
main.cpp
#include <iostream>
#include <string>
using namespace std;
void echo(string);
int main()
{
echo("hello");
cout << "Hello world!" << endl;
return 0;
}
print.cpp
#include <iostream>
#include <string>
void echo(string code){
cout << code;
}
After compiling the code in code blocks 12.11, it gives me that error:
undefined reference to `echo(std::string)
I use windows 7 x64.
I have added the directory; Project>build options > search directories and added the current working directory.
All the files are in one console project in code blocks
I believe you should read up a bit more on namespaces usage. You are missing std in print.cpp.
Generally, while starting to learn cpp or getting a grip of the language you should always try writing full names of the classes along with the namespaces. Eventually with practice and some oversights (like now) you will learn why you really need them. In a nutshell namespaces are great:
When you are writing code over multiple files
Compartmentalize your code into separate blocks.
Also, using namespace std; should be used within cpp files mostly (otherwise headers get mangled up.
Anyways, try changing your code to this:
#include <iostream>
#include <string>
void echo(std::string code){
std::cout << code;
}
Then your results will look like this:
> g++ main.cpp print.cpp -o a.out
> ./a.out
helloHello world!
You should get more than that linker error, since you use string without any namespace in your print.cpp file. And if that source file doesn't compile it can't be linked with, and you will get the linker error you have.
Change to e.g.
void echo(std::string code) { ... }
And you do try to link with the object file created from print.cpp ?
I know this is old, but for anyone looking to solve this issue, the following may be a solution for you. If you have g++ follow c++ 11 under project->build options (check your options anyway) then you must check that box for all files you make in the project for the error to be cleared up. I had that annoying undefined reference thing too but now it is gone!
Try "Project/Properties/Build Targets tab". There you should find "Build target files" field. In that filed find "print.cpp" and click the checkbox (now the compiler will build print.cpp).
Some usefull information on Project management in CB
http://www.codeblocks.org/docs/main_codeblocks_en.html
When dealing with strings in C++ its best to sue std::string and your code seems to be wrong with a changes like using std::cout instead of plain cout another thing you need to be careful is linking your files especially files in different directories you need to tell code blocks were to find this print.cpp by going to build option and go for the search tab directory and point to where print.cpp is other wise the other approach is to just build a project which will have the main.cpp and and then add print.cpp class to current project I hope this will be of some help
I am building a Makefile project in Eclipse Juno, and I have it set up so it compiles and debugs (it's using CMake, so I'm not using the internal tools). However, Eclipse obviously hasn't been informed of the right headers, as in the following code:
#include <iostream>
using namespace std;
int main ()
{
cout << "Hello world << endl;
return 0;
}
the include "iostream" and symbols "std", "cout" and "endl" are all unresolved.
How should I make Eclipse aware of these so it will stop underlining everything in red and spamming with errors?
This can be resolved by specifying the following environmental variables in Project->Properties->C++ Build->Environment.
LANG=en_US
LC_ALL=en_US
Apparently they are needed for the auto-discovery tools to work out where the includes live.
Answer gleaned from this Eclipse forum thread.