config: set PORTAGE_OVERRIDE_EPREFIX for subprocs

diff --git a/pym/portage/package/ebuild/config.py b/pym/portage/package/ebuild/config.py
index 87cefee61f17c800ec5bd89cb401fb84c66355be..df719e2f10d5629d80a3b9c7e21f15796aaabbbd 100644 (file)
--- a/pym/portage/package/ebuild/config.py
+++ b/pym/portage/package/ebuild/config.py
@@ -502,8 +502,13 @@ class config(object):
                        self["ROOT"] = target_root
                        self.backup_changes("ROOT")
 
+                       # The PORTAGE_OVERRIDE_EPREFIX variable propagates the EPREFIX
+                       # of this config instance to any portage commands or API
+                       # consumers running in subprocesses.
                        self["EPREFIX"] = eprefix
                        self.backup_changes("EPREFIX")
+                       self["PORTAGE_OVERRIDE_EPREFIX"] = eprefix
+                       self.backup_changes("PORTAGE_OVERRIDE_EPREFIX")
                        self["EROOT"] = eroot
                        self.backup_changes("EROOT")