You could tell eclipse that USE_FEATURE_A
is defined. Open your project properties and go to the "C/C++ General->Paths and Symbols" page, under the "Symbols" tab click the "Add" button and put USE_FEATURE_A
in the name feild and click OK.
Note: this will cause it not to index any #else
sides to your preprocessor stuff... so unless they are all like the one in question you can't AFAIK, but if they are they you're good. (Eclipse contains a C preprocessor that it uses to analyize your code all the stuff above does is essentially the same as adding -DUSE_FEATURE_A to your command line so Eclipse's preprocessor will behave differently from the one in your compiler)