eclipse C project shows errors (Symbol could not be resolved) but it compiles

I have got access to a C project at work that I have to implement some stuff in. I was able to load it into eclipse and can `Project -> Build All` it. Compilation shows no errors or warnings. But in eclipse, there are a lot of errors shown. One example:

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There is an enum

typedef enum MeasurementType {
PN, BB, AM, RES
} MEAS_TYPE;
MEAS_TYPE type;

in one of the files. It is used somewhere else and produces an error like this:
![enter image description here][1]

It is most interesting, that only `AM` seems to be a problem, not `PN` or `BB`.

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I haven't found a satisfying solution to this. I already tried to include all possible directories I could think of in `Project Properties -> C/C++ General -> Paths and Symbols` (like [this post][2] suggests), but that didn't help.

The project itself is compiled with Makefiles (which is why I need `Project -> Build All`). Can it be that eclipse does not interpret those Makefiles correctly or something? I am a bit lost after messing around with that stuff for a few hours and not getting a single step forward.

EDIT: Here are some screenshots for my build-relevant project properties (at least I believe they are relevent :D). Tell me if you need more information.

![enter image description here][3] ![enter image description here][4]


[1]:

[2]:

[To see links please register here]

[3]:

[4]:

It looks as if Eclipse (not gcc) is setup to parse the wrong or some additonally, propably outdated (include) source files.

Since I got a suggestion from moooeeeep, I will post the solution here. I am still accepting alk's answer, because he was the one that showed me towards the right direction.

**My solution:**

If I click on `AM` in eclipse (the one that is underlined with red) and press `F3` to go to the declaration, it actually asked me to which declaration I want to go. It listed the (correct) enum constant as well as some variable from somewhere else. Therefore the problem was that multiple declarations of `AM` were present in different code locations.

I fixed this problem by just **renaming** the `enum` constant to something else (`AN` in my case). There is no variable with the same name in the code and therefore eclipse was able to refactor it correctly.

There is a bug report added in Eclipse CDT Bugzilla with regard to this problem:

[To see links please register here]

This is quite an old question, but I hope this short answer can be useful to someone.

I was having similar errors with enums in the IDE but not when compiling, which seemed to indicate a bug in Eclipse's Codan. After upgrading to the new version of Eclipse (Neon 4.6) released in June, the errors have disappeared. Just try updating Eclipse!