diff --git a/rpython/translator/platform/posix.py b/rpython/translator/platform/posix.py
index d53449a..4463831 100644
--- a/rpython/translator/platform/posix.py
+++ b/rpython/translator/platform/posix.py
@@ -62,7 +62,8 @@ class BasePosix(Platform):
 
     def _pkg_config(self, lib, opt, default, check_result_dir=False):
         try:
-            ret, out, err = _run_subprocess("pkg-config", [lib, opt])
+            pkg_config = os.environ.get('PKG_CONFIG', 'pkg-config')
+            ret, out, err = _run_subprocess(pkg_config, [lib, opt])
         except OSError as e:
             err = str(e)
             ret = 1