diff --git a/lisp/llvm-lib/llvm-act-on-file/act-on-c-file.el b/lisp/llvm-lib/llvm-act-on-file/act-on-c-file.el
index f930ff1..afa7147 100644
--- a/lisp/llvm-lib/llvm-act-on-file/act-on-c-file.el
+++ b/lisp/llvm-lib/llvm-act-on-file/act-on-c-file.el
@@ -79,12 +79,14 @@
               :compiler compiler
               :file file
               :action compiler-action
-              :output output)
-             (pcase action
-               ('debug (format "-mllvm -debug-only=%s" (ll/read-pass-name "Which pass? ")))
-               ('before-after (let ((pass (ll/read-pass-name "Which pass? ")))
-                                (format "-mllvm -print-before=%s -mllvm -print-after=%s" pass pass)))
-               ('changed "-mllvm -print-before-all"))
+              :output output
+              :flags
+              (list
+               (pcase action
+                 ('debug (format "-mllvm -debug-only=%s" (ll/read-pass-name "Which pass? ")))
+                 ('before-after (let ((pass (ll/read-pass-name "Which pass? ")))
+                                  (format "-mllvm -print-before=%s -mllvm -print-after=%s" pass pass)))
+                 ('changed "-mllvm -print-before-all"))))
              " ")
        " "))))
 
diff --git a/lisp/llvm-lib/llvm-shared.el b/lisp/llvm-lib/llvm-shared.el
index dd1ba03..29975a3 100644
--- a/lisp/llvm-lib/llvm-shared.el
+++ b/lisp/llvm-lib/llvm-shared.el
@@ -247,8 +247,8 @@
   (apply (lls/conf-get 'dis-command-fun) args))
 
 ;; ========================= LLVM Build Dirs =========================
-(cl-defun lls/default-comp-fun (&key compiler file action output rest)
-  (string-join
+(cl-defun lls/default-comp-fun (&key compiler file action output flags)
+  (-->
    (list compiler
          (lls/get-clang-options)
          (string-join rest " ")
@@ -259,11 +259,13 @@
            ('preprocess "-E")
            ('llvm-ir "-S -emit-llvm")
            ('executable ""))
+         flags
          "-o -"
          (or (and output
                   (format "| tee %s" output))
              ""))
-   " "))
+   (flatten-list it)
+   (string-join it " ")))
 
 (defun ll/read-pass ()
   (completing-read "Which pass? "