diff --git a/var/spack/repos/builtin/packages/freetype/package.py b/var/spack/repos/builtin/packages/freetype/package.py
index 189dbc7e950..4446ba5666b 100644
--- a/var/spack/repos/builtin/packages/freetype/package.py
+++ b/var/spack/repos/builtin/packages/freetype/package.py
@@ -39,6 +39,7 @@ class Freetype(AutotoolsPackage):
 
     depends_on('libpng')
     depends_on('bzip2')
-
+    depends_on('pkg-config@0.9.0:', type='build')
+  
     def configure_args(self):
         return ['--with-harfbuzz=no']
diff --git a/var/spack/repos/builtin/packages/libxml2/package.py b/var/spack/repos/builtin/packages/libxml2/package.py
index 0b55fe4d305..bbb934ab9fa 100644
--- a/var/spack/repos/builtin/packages/libxml2/package.py
+++ b/var/spack/repos/builtin/packages/libxml2/package.py
@@ -43,6 +43,8 @@ class Libxml2(Package):
     depends_on('zlib')
     depends_on('xz')
 
+    depends_on('pkg-config@0.9.0:', type='build')
+
     def install(self, spec, prefix):
         if '+python' in spec:
             python_args = [