title: Resolving p2 dependencies in an Eclipse product
body: <p>I am trying to install a feature (<code>com.iar.cdt.arm.sdk.feature</code>) in an Eclipse product (<code>MCUXpressoIDE</code>).
  The feature has a requirement on another feature (<code>org.eclipse.emf.feature</code>, with no version specified) which is part of the product itself (in version 2.19, as <code>org.eclipse.emf.common.feature</code>). Despite this, p2 is trying to fetch the same feature from one of the available update sites, resulting in a conflict and installation error.</p>
  <p>Does p2 consider the product itself as a source for needed features, in addition to the update sites? If not, why?</p>
  <p>EDIT: It does, see the <a href="https://stackoverflow.com/a/63830538/885586">accepted answer</a></p>
  <p>The original installation exception follows:</p>
  <pre><code> Cannot complete the install because of a conflicting dependency.
   Software being installed: IAR Toolchain for ARM (8.30.x - 8.50.x) 8.1.0.202007252323 (com.iar.cdt.arm.sdk.feature.feature.group 8.1.0.202007252323)
   Software currently installed: MCUXpresso IDE 11.2.0.202007071544 (MCUXpressoIDE 11.2.0.202007071544)
   Only one of the following can be installed at once:
   EMF Common 2.17.0.v20190920-0401 (org.eclipse.emf.common.feature.jar 2.17.0.v20190920-0401)
   EMF Common 2.19.0.v20200324-0932 (org.eclipse.emf.common.feature.jar 2.19.0.v20200324-0932)
   Cannot satisfy dependency:
   From: MCUXpresso IDE 11.2.0.202007071544 (MCUXpressoIDE 11.2.0.202007071544)
   To: org.eclipse.equinox.p2.iu; org.eclipse.emf.common.feature.group [2.19.0.v20200324-0932,2.19.0.v20200324-0932]
   Cannot satisfy dependency:
   From: IAR Toolchain for ARM (8.30.x - 8.50.x) 8.1.0.202007252323 (com.iar.cdt.arm.sdk.feature.feature.group 8.1.0.202007252323)
   To: org.eclipse.equinox.p2.iu; org.eclipse.emf.feature.group 0.0.0
   Cannot satisfy dependency:
   From: EMF Common 2.17.0.v20190920-0401 (org.eclipse.emf.common.feature.group 2.17.0.v20190920-0401)
   To: org.eclipse.equinox.p2.iu; org.eclipse.emf.common.feature.jar [2.17.0.v20190920-0401,2.17.0.v20190920-0401]
   Cannot satisfy dependency:
   From: EMF Common 2.19.0.v20200324-0932 (org.eclipse.emf.common.feature.group 2.19.0.v20200324-0932)
   To: org.eclipse.equinox.p2.iu; org.eclipse.emf.common.feature.jar [2.19.0.v20200324-0932,2.19.0.v20200324-0932]
   Cannot satisfy dependency:
   From: EMF - Eclipse Modeling Framework Runtime and Tools 2.20.0.v20191028-0905 (org.eclipse.emf.feature.group 2.20.0.v20191028-0905)
   To: org.eclipse.equinox.p2.iu; org.eclipse.emf.common.feature.group [2.17.0.v20190920-0401,2.17.0.v20190920-0401]
  </code></pre>