diff --git a/lib/spack/spack/util/executable.py b/lib/spack/spack/util/executable.py
index 3457ea9bff3..c424b9cdb55 100644
--- a/lib/spack/spack/util/executable.py
+++ b/lib/spack/spack/util/executable.py
@@ -178,7 +178,7 @@ def streamify(arg, mode):
         istream, close_istream = streamify(input,  'r')
 
         if not ignore_quotes:
-            quoted_args = [arg for arg in args if re.search(r'^"|^\'|"$|\'$', arg)]
+            quoted_args = [arg for arg in args if re.search(r'^".*"$|^\'.*\'$', arg)]
             if quoted_args:
                 tty.warn(
                     "Quotes in command arguments can confuse scripts like"