I've loaded a C++ project into Eclipse (Europa) and I'm familiarizing myself with the CDT interface.
There is one particularly annoying error message for the following line:
#include "somedir/somefile.h"
somedir/somefile.h: No such file or directory
The include file exists in "/opt/local/project/include/somedir/somefile.h".
Under Project > Properties > C/C++ General > Paths and Symbols > Includes, I've already added the include directory "/opt/local/project/include".
However, this does not seem to solve the issue.
Does anyone know how to deal with this error?
Thanks.
Edit:
Solved the problem. Turns out that it was a simple issue. I had to "refresh" all the projects in the workspace.
Why such an old version? Newer versions of the Eclipse CDT have made vast improvements.
This is a really obvious question, but under Project > Properties > C/C++ General > Paths and Symbols > Includes (at least in the current CDT), there are separate categories for each language (assembly, C, and C++). Did you make sure to add /opt/local/project/include under both C and C++ (if appropriate)?
Alternatively, if your project is built using Make, then simply building your project from within Eclipse will often let Eclipse auto-detect include directories using Make's output, without your having to set the include paths yourself.
If the paths are all set up correctly, then the standard fix for indexing-related problems is to right-click on your project, choose Index, and choose Rebuild.
Right Click on project -> Index -> Freshen All Files.
Related
I'm trying to build a project that uses an external library (Casablanca) using Eclipse CDT 8.8.1. on Mac OS. As expected, the first build run returned "cpprest/http_client.h file not found" errors.
I then proceeded to add an include path (/Users/me/projects/casablanca/Release/include) by right-clicking on the project, selecting Properties->C/C++ Include Paths and Symbols, Add External Include Path, and moving it up in priority as the first listed folder.
However this did not solve the problem and Eclipse still can't seem to find the headers. The #include directive is as below:
#include <cpprest/http_client.h>
and the added /include directory does have a /cpprest sub-directory, with http_client.h in it.
Any help would be appreciated.
Adding an include path to Project Properties | C/C++ General | Paths and Symbols only adds the include path to the set of includes searched by CDT's indexer when indexing the project.
The actual build system needs to be told the include path by another means. If you're using a Managed Build project (as opposed to a Makefile project) - which it sounds like you are - you would add the include path in Project Properties | C/C++ Build | Settings. Note that the indexer automatically picks up build settings, so once you do this, there shouldn't be a need to also add it to Paths and Symbols.
This answer applies if:
You do not have a C++ Managed Build Project (for example, you have a C++ Makefile project as I do).
and
Various things in the code editor are underlined in red because a header file is not detected.
In my case, the indexer found the headers (and all the red underlines went away) when I added the include directories to Project Properties > C/C++ General > Preprocessor Includes > Select GNU C++ > Select CDT User Settings Entries > Press Add. Make sure the combo boxes (aka drop down menus) are set to "Include Directory" and "File System Path". Type in or browse for the include directory. Then press OK > OK.
Note that prior to this I tried adding the include directory to Project Properties > C/C++ General > Paths and Symbols > GNU C++ > Add, but this did not solve the problem alone.
Based on some quick testing it seems that the Paths and Symbols > GNU C++ > etc includes are unnecessary assuming you are using an external build system.
I am using Eclipse 3.8.1 on Ubuntu 16.04 with Eclipse CDT 8.6.0.
I'm trying to build a project that uses an external library (Casablanca) using Eclipse CDT 8.8.1. on Mac OS. As expected, the first build run returned "cpprest/http_client.h file not found" errors.
I then proceeded to add an include path (/Users/me/projects/casablanca/Release/include) by right-clicking on the project, selecting Properties->C/C++ Include Paths and Symbols, Add External Include Path, and moving it up in priority as the first listed folder.
However this did not solve the problem and Eclipse still can't seem to find the headers. The #include directive is as below:
#include <cpprest/http_client.h>
and the added /include directory does have a /cpprest sub-directory, with http_client.h in it.
Any help would be appreciated.
Adding an include path to Project Properties | C/C++ General | Paths and Symbols only adds the include path to the set of includes searched by CDT's indexer when indexing the project.
The actual build system needs to be told the include path by another means. If you're using a Managed Build project (as opposed to a Makefile project) - which it sounds like you are - you would add the include path in Project Properties | C/C++ Build | Settings. Note that the indexer automatically picks up build settings, so once you do this, there shouldn't be a need to also add it to Paths and Symbols.
This answer applies if:
You do not have a C++ Managed Build Project (for example, you have a C++ Makefile project as I do).
and
Various things in the code editor are underlined in red because a header file is not detected.
In my case, the indexer found the headers (and all the red underlines went away) when I added the include directories to Project Properties > C/C++ General > Preprocessor Includes > Select GNU C++ > Select CDT User Settings Entries > Press Add. Make sure the combo boxes (aka drop down menus) are set to "Include Directory" and "File System Path". Type in or browse for the include directory. Then press OK > OK.
Note that prior to this I tried adding the include directory to Project Properties > C/C++ General > Paths and Symbols > GNU C++ > Add, but this did not solve the problem alone.
Based on some quick testing it seems that the Paths and Symbols > GNU C++ > etc includes are unnecessary assuming you are using an external build system.
I am using Eclipse 3.8.1 on Ubuntu 16.04 with Eclipse CDT 8.6.0.
The error is as above. I have what should be all the necessary files include in the eclipse project:
/usr/include/c++/4.6
/usr/include
/usr/include/linux
/usr/local/include
etc.
I tried std::cout and using namespace std; cout but it still says unresolved.
I have imported iostream and cstdlib.
Also, I'm on Ubuntu 12.04 with eclipse 3.7.2.
Code snippet:
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include "XPLMDisplay.h"
#include "XPLMGraphics.h"
int XPluginStart(char * outName, char * outSig, char * outDesc) {
/* ... */
std::cout << "test" << std::endl;
/* ... */
}
using namespace std;
UPDATE: I had created the eclipse project from existing code. Creating a new c++ project fixes it. I'll accept an answer that explains what setting in the existing project could cause this (so I don't have to cut & paste all my projects).
Most likely you have some system-specific include directories missing in your settings which makes it impossible for indexer to correctly parse iostream, thus the errors. Selecting Index -> Search For Unresolved Includes in the context menu of the project will give you the list of unresolved includes which you can search in /usr/include and add containing directories to C++ Include Paths and Symbols in Project Properties.
On my system I had to add /usr/include/c++/4.6/x86_64-linux-gnu for bits/c++config.h to be resolved and a few more directories.
Don't forget to rebuild the index (Index -> Rebuild) after adding include directories.
To get rid of symbol warnings you don't want, first you should understand how Eclipse CDT normally comes up with unknown symbol warnings in the first place. This is its process, more or less:
Eclipse detects the GCC toolchains available on the system
Your Eclipse project is configured to use a particular toolchain
Eclipse does discovery on the toolchain to find its include paths and built-in defines, i.e. by running it with relevant options and reading the output
Eclipse reads the header files from the include paths
Eclipse indexes the source code in your project
Eclipse shows warnings about unresolved symbols in the editor
It might be better in the long run to fix problems with the earlier steps rather than to override their results by manually adding include directories, symbols, etc.
Toolchains
If you have GCC installed, and Eclipse has detected it, it should list that GCC as a toolchain choice that a new C++ project could use, which will also show up in Window -> Preferences -> C/C++ -> New CDT Project Wizard on the Preferred Toolchains tab's Toolchains box on the right side. If it's not showing up, see the CDT FAQ's answer about compilers that need special environments (as well as MinGW and Cygwin answers for the Windows folk.)
If you have an existing Eclipse C++ project, you can change the associated toolchain by opening the project properties, and going to C/C++ Build -> Tool Chain Editor and choosing the toolchain you want from the Current toolchain: pulldown. (You'll have to uncheck the Display compatible toolchains only box first if the toolchain you want is different enough from the one that was previously set in the project.)
If you added a toolchain to the system after launching Eclipse, you will need to restart it for it to detect the toolchain.
Discovery
Then, if the project's C/C++ Build -> Discovery Options -> Discovery profiles scope is set to Per Language, during the next build the new toolchain associated with the project will be used for auto-discovery of include paths and symbols, and will be used to update the "built-in" paths and symbols that show up in the project's C/C++ General -> Paths and Symbols in the Includes and Symbols tabs.
Indexing
Sometimes you need to re-index again after setting the toolchain and doing a build to get the old symbol warnings to go away; right-click on the project folder and go to Index -> Rebuild to do it.
(tested with Eclipse 3.7.2 / CDT 8)
Thanks loads for the answers above. I'm adding an answer for a specific use-case...
On a project with two target architectures each with its own build configuration (the main target is an embedded AVR platform; the second target is my local Linux PC for running unit tests) I found it necessary to set Preferences -> C/C++ -> Indexer -> Use active build configuration as well as to add /usr/include/c++/4.7, /usr/include and /usr/include/c++/4.7/x86_64-linux-gnu to Project Properties -> C/C++ General -> Paths and Symbols and then to rebuild the index.
I tried the marked solution here first. It worked but it is kind hacky, and you need to redo it every time you update the gcc. I finally find a better solution by doing the followings:
Project -> Properties -> C/C++ General -> Preprocessor Include Paths, Macros, etc.
Providers -> CDT GCC built-in compiler settings
Uncheck Use global provider shared between projects (you can also modify the global provider if it fits your need)
In Command to get compiler specs, add -std=c++11 at the end
Index->Rebuild
Voila, easy and simple. Hopefully this helps.
Note: I am on Kepler. I am not sure if this works on earlier Eclipse.
I am using Ubuntu 12.04 / Eclipse 4.2.1 / CDT 8.1.1 and I used to have the same problem for quite some time: importing a C++ project from SVN would cause these annoying "Unresolved inclusion" errors and I would instead have to create a new project and copy the files in there as a work-around (still partial, since SVN functionality would not be there!).
At last, I have just found a simple, satisfactory solution:
Go to Project -> Properties -> C/C++ General -> Preprocessor Include Paths, Macros etc. -> Providers and check Enable language settings providers for this project.
Restart Eclipse.
Hopefully that already does the trick.
I had a similar problem with *std::shared_ptr* with Eclipse using MinGW and gcc 4.8.1. No matter what, Eclipse would not resolve *shared_ptr*. To fix this, I manually added the __cplusplus macro to the C++ symbols and - viola! - Eclipse can find it. Since I specified -std=c++11 as a compile option, I (ahem) assumed that the Eclipse code analyzer would use that option as well. So, to fix this:
Project Context -> C/C++ General -> Paths and Symbols -> Symbols Tab
Select C++ in the Languages panel.
Add symbol __cplusplus with a value of 201103.
The only problem with this is that gcc will complain that the symbol is already defined(!) but the compile will complete as before.
For me it helped to enable the automated discovery in Properties -> C/C++-Build -> Discovery Options to resolve this problem.
I simply delete all error in the buttom: problem list.
then close project
and reopen project
clean project
build all
run
then those stupids errors go.
If all else fails, like it did in my case, then just disable annotations. I started a c++11 project with own makefile but couldn't fix all the problems. Even if you disable annotations, eclipse will still be able to help you do some autocompletion. Most importantly, the debugger still works!
I had the same issue using Eclipse CDT (Kepler) on Windows with Cygwin installed. After pointing the project properties at every Cygwin include I could think of, it still couldn't find cout.
The final missing piece turned out to be C:cygwin64\lib\gcc\x86_64-pc-cygwin\4.8.2\install-tool\include.
To sum up:
Right click on the project
Choose Properties
Navigate to C/C++ General > Paths and Symbols > Includes tab
Click Add...
Click File system...
Browse to the location of your Cygwin lib\gcc\x86_64-pc-cygwin\4.8.2\install-tool\include
Click OK
Here is what my project includes ended up looking like when it was all said and done:
You guys are looking under the wrong section.
I realized the difference when I installed in Linux after recently getting frustrated with Windows and the difference was immediately apparent.
In the new setup I have an includes folder in a projected that I created out of existing source. I can expand this and see a ton of includes; however, I cannot add to them.
This lead me to a hunt for where these files were being listed.
They're listed under the Project Properties > C/C++ General > Preprocessor Includes > GNU C++
CDT GCC Built-in Compiler Settings [Shared]
Under that is a ton of includes.
These settings are set by the toolchain you've selected.
I have created the Makefile project using cmake on Ubuntu 16.04.
When created the eclipse project for the Makefiles which cmake generated I created the new project like so:
File --> new --> Makefile project with existing code.
Only after couple of times doing that I have noticed that the default setting for the "Toolchain for indexer settings" is none.
In my case I have changed it to Linux GCC and all the errors disappeared.
Hope it helps and let me know if it is not a legit solution.
Cheers,
Guy.
I had this happen after updating gcc and eclipse on ArchLinux. What solved it for me was Project -> C/C++ Index -> Rebuild.
Just adding yet another bit of advice after trying a bunch of stuff myself and it not working....
I had GCC installed and the path to the includes set correctly. Had the std error as well, and couldn't get anything working for cout (and I suspect anything in the SL...)
Took me awhile to realize that g++ wasn't installed - gcc was but not g++. So just do:
sudo apt-get install g++
Restart eclipse. Assuming above mentioned details about gcc & paths to includes are fine, you should be okay now...
mine was bit easy to fig out right click >run as>run configration
check boxes include system lib,inherited mains
I have locally forked (via hg clone) a C/C++ (Eclipse CDT) project and imported it into my Eclipse workspace. My editor window for the forked project now looks like this:
Clearly, these are not real errors, since the code builds correctly. Also, these errors are not marked in the original project from which this one was forked.
Why does Eclipse think there are errors in this source?
EDIT: Eclipse error messages when hovering over the "bugs" are, e.g., Type int64_t could not be resolved and symbol 'cout' could not be resolved.
EDIT: I've noticed that Eclipse usually shows a "folder" named includes in the project. It is missing for this project. How can I get it back?
Eclipse has to know the paths where to find the include files. This may be set using general eclipse settings or project by project.
For some reason it seems like the default paths are not set for your current project.
What you can do:
Open the project settings and go to C/C++ General -> Paths and Symbols (at least that is how it is called in my eclipse version) and fix the include directories.
Maybe it is enough to load the default configuration for that specific project. Maybe you have to set up your include pathes by yourself. On Unix / OS X this should usually be usr/include. On Windows I have no idea, but that should be easy to find out.
Afterwards it may be necessary that your rebuild your eclipse index (right click on your project, then index -> rebuild).
If that does not help please share a screenshot of the Paths and Symbols dialog of your project.
Also see the eclipse documentation on this topic.
I had to include
CDT Cross GCC Built-in Compiler Settings
CDT GCC Built in Compiler Settings [ Shared ]
in Properties for the project -> C/C++ General -> Preprocessor Include Paths, Macros etc. -> Providers
add this define in Eclipse to Project Properties->C/C++ General->Paths and Symbols
__STDC_FORMAT_MACROS
Rebuild your eclipse index. It will work.
This worked on Mac OS X Yosemite 10.10.5, Eclipse version Mars.1 Release (4.5.1):
Since the includes are usually discovered by Eclipse through the toolchain, check that you have an actual toolchain set (when I ran into this problem after importing a project, the toolchain was set to "No toolchain."):
Project -> Properties -> C/C++ Build -> Tool Chain Editor -> Current toolchain
If no toolchains appear in the dropdown, try unchecking "Display compatible toolchains only" and choosing a toolchain (I chose Cross GCC). When I saved the changes and re-opened the project properties to look at this field again, "Display compatible toolchains only" was automatically re-checked.
Then re-index the project:
Project -> C/C++ Index -> Rebuild
This solved the problem for me (the "pseudo-errors" disappeared, and the includes "folder" appeared under my project in the file system view).
Have you #included the correct files in your code? For std::cout it would be:
#include <iostream>
and for int64_t:
#include stdint.h
I am getting this error in the TestExecute.cpp -
"Symbol 'std' could not be resolved"
CODE
#include <iostream>
using namespace std;
I just created a executable project in Eclipse (in Windows 7) as shown below. It seems like I am selecting a toolchain that is not supported. Is it so? I have installed Cygwin and it is available in preferences.
EDIT: Based on #RobertoWilko comment, removing the line "using namespace std;
" removed the error. But the binary is not created. "Launch Failed. Binary not found". How to correct this?
Try out this step: https://www.eclipse.org/forums/index.php/t/636348/
Go to
Project -> Properties -> C/C++ General -> Preprocessor Include Paths, Macros, etc. -> Providers
Activate CDT GCC Built-in Compiler Settings
Deactivate Use global provider shared between projects
Add the command line argument -std=c++11.
I do not know whether you have solved this problem but I want to post my solution for those might ran into the same problem.
First, make sure that you have the "Includes" folder in your Project Explorer. If you do not have it, go to second step. If you have it, go to third step.
Second, Window -> Preferences-> C/C++- > Build >Environment: Create two environment variables:
a) Name: C_INCLUDE_PATH Value: /usr/include
b) Name: CPLUS_INCLUDE_PATH Value: /usr/include/c++
Go to Cygwin/usr/include/, if you cannot find folder "c++", copy it from \cygwin\lib\gcc\i686-pc-cygwin\X.X.X\include and Then restart your Eclipse.
Third, Right Click your project in Project Explorer -> Properties -> C/C++ General -> Paths and Symbols -> Includes -> Languages:GNU C++
If you can find some C++ folders in the "Include directories" then click Apply and OK. Change a bit your codes, and save it.
You will find there will be not symbol could not be resolved problems.
I documented my solution, hoping someone might get benefits.
You can rewrite the code likes this:
#include<iostream>
#include<stdio.h>
using namespace std;
For MinGW this worked for me:
Right click project, select Properties
Go to C/C++ General - Paths and Symbols - Includes - GNU C++ - Include directories
Select Add...
Select Variables...
Select MINGW_HOME and click OK
Click Apply and OK
You should now see several MinGW paths in Includes in your project explorer.
The errors may not disappear instantly, you may need to refresh/build your project.
If you are using Cygwin, there could be an equivalent variable present.
The includes folder in the project is probably missing /usr/include/c++.
Goto your project in project explorer, right click -> Properties -> C\C++ Build -> Environment -> add -> value= /usr/include/c++. Restart eclipse.
What allowed me to fix the problem was going to: Project -> Properties -> C/C++ General -> Preprocessor Include Paths, Macros, etc. -> Providers -> CDT GCC built-in compiler settings, enabling that and disabling the CDT Cross GCC Built-in Compiler Settings
Install C++ SDK:
Help > Install New Software > Work with: path for your eclipse version > search for C++ and install C++ sdk development tools.
Example for a path: Mars - http://download.eclipse.org/releases/mars
I was having this problem using Eclipse Neon on Kubuntu with a 16.04 kernel, I had to change my #include <stdlib.h> to #include <cstdlib> this made the std namespace "visible" to Eclipse and removed the error.
This worked for me on Eclipse IDE for C/C++ Developers Version: 2020-03 (4.15.0) Build id: 20200313-1211. Also, my code is cross-compiled.
Create a new project making sure it's created as a cross-compiled solution. You have to add the /usr/bin directory that matches your cross-compiler location.
Add the C and C++ headers for the cross-compiler in the Project Properties.
For C: Project > Properties > C/C++ General > Paths and Symbols > Includes > GNU C. Add... -> The path to your /usr/include directory from your cross-compiler.
For C++: Project > Properties > C/C++ General > Paths and Symbols > Includes > GNU C++. Add... -> The path to your /usr/include/c++/ directory from your cross-compiler.
If you don't know your gcc version, type this in a console (make sure it's your cross gcc binary):
gcc -v
Modify the dialect for the cross-compilers (this was the trick).
For C: Project > Properties > C/C++ Build > Settings > Tool Settings > Cross GCC Compiler > Dialect. Set to ISO C99 (-std=C99) or whatever fits your C files standard.
For C++: Project > Properties > C/C++ Build > Settings > Tool Settings > Cross G++ Compiler > Dialect. Set to ISO C++14 (-std=c++14) or whatever fits your C++ files standard.
If needed, re-index all your project by right-clicking the project > Index > Rebuild.
The problem you are reporting seems to me caused by the following:
you are trying to compile C code and the source file has .cpp extension
you are trying to compile C++ code and the source file has .c extension
In such situation Eclipse cannot recognize the proper compiler to use.
Try restart Eclipse first, in my case I change different Compiler setting of the project then it shows this message, after restart it works.