Eclipse can't find include file in subdirectory - c++

After importing a c++ Makefile-project into Eclipse, my project depends on some libraries which are located in /usr/include/gazebo-2.2/gazebo.
These are included via the line #include < gazebo/xx/xx.hh>. CMake doesn't have a problem finding the files, Eclipse unfortunately does...
In my include folder, the folder /usr/include/ is set as include path. However it can't find the include files.
Is it possible for eclipse to discover the files without adding the full path to the include directories?

Is it possible for eclipse to discover the files without adding the full path to the include directories?
Since you are using a Makefile project, presumably your makefile specifies the relevant include path. Eclipse can pick this up using its Build Output Parser. The general way to set this up is:
Make sure your makefile can produce output that includes the full compiler command invocations (e.g. gcc -I /usr/include/gazebo-2.2 ... - since this is what the build output parser needs to see), or can be configured to produce that output.
Make sure Eclipse is configured to invoke your makefile correctly (in terms of invocation directory and target name) in Project Properties -> C/C++ Build.
Make sure the build output parser is enabled in Project Properties -> C/C++ General -> Preprocessor Include Paths, Macros etc. -> Providers tab. If necessary, adjust the "Compiler command pattern" as appropriate.
Perform a build from within Eclipse. Assuming your build is successful (or at least succesful enough for the build output to contain the compiler commands for every source file), the build output parser should then pick up information such as include paths and macros defined on the command line. In the Project Explorer, source files for which settings were picked up in this way will be annotated with a little wrench decoration on the icon.
At this point, your includes should be resolved. You may need to re-build the index to get Eclipse to process the contents of the newly resolved files.
For completeness, since you mentioned CMake, I'll mention that there also exist plugins that will configure a project's include paths directly based on CMakeLists.txt. (I can't recommend a specific one because I don't use CMake myself, but searching for "CMake" in the Eclipse Marketplace should give you several options.)

Is it possible for eclipse to discover the files without adding the full path to the include directories?
No, not unless the include path in question is one of the compiler's default include
paths, which is not so in your case.
If your want the compiler to find the header file referred to by e.g.
<gazebo/xx/xx.hh>
when the required file is:
/usr/include/gazebo-2.2/gazebo/xx/xx.h
then the compiler must be given the include path:
/usr/include/gazebo-2.2
which should appear in compiler commandlines in your build log as:
-I/usr/include/gazebo-2.2
I notice also that your example is actually:
#include < gazebo/xx/xx.hh>
not:
#include <gazebo/xx/xx.hh>
In your example, the leading space will be considered part of the
filename and the header would not be found.

Related

Build failed with no stated reason on Segger Embedded Studio after adding custom source files

I'm modifying a simple example project (blinky) from the nRF SDK. I added a header file and a .c file in a new folder inside the project directory then added that path ./lib to the common preprocessor user include directories. I then included the header to main.c.
I can compile the new library on its own but when I build the whole project, I get Build failed error with no stated reason to follow up.
Here is an image of that:
Does anyone here know how to beat this?
I haven't used Segger Studio specifically, but it seems to be the CrossWorks IDE underneath.
In CrossWorks, you have to do the following:
Download & install all relevant libs from inside the IDE, under Tools -> Packages -> Install packages. Grab your specific target MCU as well as any specific boards or libraries you'll be using. In case some needed lib is missing here, you will get very weird errors.
In the project, click on the project name itself in "project explorer". Then in the properties window, check settings (this is a bit different in different versions of CrossWorks, might have to right click and pick properties in older versions). Under "user include directories" you should have something like this:
$(DeviceIncludePath)
$(TargetsDir)/NameOfMCU/Include
$(PackagesDir)/CMSIS_4/CMSIS/Include
$(ProjectDir)/NameOfDirectory
Where "NameOfMCU" is the name of the MCU family used, CMSIS should be there in case you are using any ARM, "NameOfDirectory" is the name of your custom directory (you can add several).
Also, get the debug build working first, before switching to release build.

Eclipse can't find header file, even though include paths are set

This was an issue we've been dealing with for a while now - we're building a C++ project using the Cygwin toolchain, and no matter what we add in the C++ compiler include paths under project settings, Eclipse can't seem to find the necessary header files.
We have done everything the Stackoverflow community has suggested so far;
Made sure include paths were workspace-relative
Tried backslashes and forward slashes
Tried using Cygwin-specific paths (/cygdrive/c instead of C:/)
Checked the compiler output to verify include paths are there
Checked the generated makefiles to make sure they're correct
Rebuilt the index
Deleted the debug folder entirely
restarted Eclipse
Basically nothing short of changing the #include <...> code itself to use a full path (C:/.../file.h) worked. This doesn't work for our needs as we need multiple developers to be able to work on this project, and the files themselves are generated dynamically as a result of some of our build procedures.
So here's a fun little detail about Eclipse we didn't know - specific source files themselves can have their own settings.
If you look at your source files and see the following wrench icon, this means that file has some settings which may be contrary to your project-specific settings.
As a result, our source-specific settings were overriding the include paths, so for those files, none of the headers could be found. The best part is that Eclipse doesn't tell you in any way more explicit than this - the wrench icon does not offer a tool-tip to explain what's going on.
Simply right click on the file > go to Resource Configurations > Reset to Default...
Your header files will be found now, provided that you've written the correct include paths in your project settings.
For reference, we're using Eclipse Kepler - I'm not sure if they fixed this and added more info for users in newer versions.

Is there a way to add include directory from C++ code?

I have a project whose vcxproj file is auto generated prior of compilation by using a script during the build process.
this project dependes on a boost library which is installed in a known location on the build machine.
the project header file declares:
#include "boost/foreach.hpp"
which forces me to manually add the path to the boost root folder to the Additional Include Directories field in the vcxproj file.
As the project file is auto-generated it forces me to split the build process into two stages and edit the project file in between.
i have also tried to change the source file and add the full path in the #include statement:
#include "<path to boost root>/boost/foreach.hpp"
but then some boost internal include fails. Which means i can't proceed in this way.
I have read through Set #include directory from C++ code file to find there is no option to add the path from code.
As I'm now on VS2012/C++11 environment i wonder if anything changed in VS2012 / C++11?
Is it still impossible to add an Include directory using a code statement?
You mean dynamically? No, there is no way. The reason is simple:
When you are running your program, it's already compiled, hence the compiler has to know about all the files to include at compile time.
It seems you're using CMake. If that's the case, I recommend you to add the include dirs in the CMake file.
Firstly, doing this:
#include "<path to boost root>/boost/foreach.hpp"
should be strongly discouraged. By doing that, you're making your source code build-able only on your environment - as your project grows, it will be a nightmare to change the path, or for other developers to build it. And, as you discovered, you'll break any headers which are included further down the chain, which are using relative paths.
What kind of script is generating your project? Is it a custom one, or is it a well known build tool such as SCons or CMake? The correct solution is to fix your build script so that it generates the project with the additional include paths correctly.

Merging two directories into one virtual directory for compilation / aliasing include directories

I have code that must be shared between two executables in the same project (one build command will build them both). This code contains #ifdef preprocessor statements which change how it works in each project (a command-line macro definition is used as a switch).
The source is abstract in the sense that some headers are missing. For example, the shared file Application.cpp might include a file called gui/MainWindow.h which doesn't exist int he shared directory but does exist in the executable source directory. Or it may include a file called gui/Local.h that does exist in the shared directory.
Essentially I need the gui path to be a combination of two locations.
On unix I've done this before simply by setting up a series of file links, but this project now has windows as a target (Visual Studio). Also, I am aware of how to do this using a shared directory structure and setting compiler include switches, but I'm hoping there is a simpler way.
Any ideas?
I use CMake for the build generation and GCC and Visual Studio as compilers.
I've already looked at defining a directory for the preprocessor, but the #include directive unfortunately cannot combine several tokens to create a filename. A single name works, and this might be an option to have cmake spit out macros for all the shared file names.
I really think the simplest solution is to use include paths - have different paths for the different projects. Look at property sheets to share settings between projects and greatly simplify the management.
If you are using file links in unix, you could do the same in Windows with symbolic links.

setup include path in eclipse CDT in mac os (headers from framework)

for example I need to include a header
#include <OpenGL/glext.h>
while it is actually a header file glext.h under OpenGL.framework/Headers/.
Therefore it is no way to give eclipse a physical path about "OpenGL/glext.h", and I always get unresolved inclusion warning.
I can still build and run them (with managed makefile project) but it is impossible to browse the functions or definitions from those "resolved" header files.
is there any solution?
While not ideal, my solution to this has been to create a folder "/Developer/Framework Headers" (though the name isn't important), and link from e.g. "/System/Library/Frameworks/Foo.framework/Headers" to "Foo" under said folder. Then in Eclipse I add "/Developer/Framework Headers" to a project's includes.
I say not ideal because apart from having to create links for the frameworks you need and add an include to each project, Eclipse seems to have trouble in certain cases such as nested frameworks (e.g. CoreGraphics beneath ApplicationServices), but YMMV.
Yes there is one. Right click on the project in "Project Explore" window and click on the "property". In there Open "C/C++ General" column and choose "Path and symbols". Now you see all of the include library path for this project. If your using C then add the OpenGL library into GNU C, or if you use C++ then add it into GNU C++. Unfortunately you have to do this for every new project. I have been searching for a while how to do this by default but nothing really useful. Hope this help you get rid of those annoying yellow wave lines.
Since current Eclipse CDT releases don't perform sub-framework header inclusion correctly, you can avoid sub-framework problems (like those generated by the CoreServices header files) by creating symbolic links to the include directories of each sub-framework. I elaborated on this subject, which stems from danhan answer on this question, in this blog post.
In order to automate this process, I've created a Z shell script which automates this process and creates the symlink to the specified frameworks' header directory, together with the links to the include directory of each one of their sub-frameworks. The script can be found in this GitHub repository.
Hope this helps.