diff --git a/guix/gexp.scm b/guix/gexp.scm
index 45cd5869f70fd53f2a03f19a7ee99dd44ddf4e2a..0d0b661c6560bcec816e9ba5915754817312de84 100644
--- a/guix/gexp.scm
+++ b/guix/gexp.scm
@@ -1005,6 +1005,15 @@ (define* (gexp->sexp exp #:key
                      (target (%current-target-system)))
   "Return (monadically) the sexp corresponding to EXP for the given OUTPUT,
 and in the current monad setting (system type, etc.)"
+  (define (self-quoting? x)
+    (letrec-syntax ((one-of (syntax-rules ()
+                              ((_) #f)
+                              ((_ pred rest ...)
+                               (or (pred x)
+                                   (one-of rest ...))))))
+      (one-of symbol? string? keyword? pair? null? array?
+              number? boolean?)))
+
   (define* (reference->sexp ref #:optional native?)
     (with-monad %store-monad
       (match ref
@@ -1034,8 +1043,10 @@ (define* (reference->sexp ref #:optional native?)
                                                   #:target target)))
              ;; OBJ must be either a derivation or a store file name.
              (return (expand thing obj output)))))
-        (($ <gexp-input> x)
+        (($ <gexp-input> (? self-quoting? x))
          (return x))
+        (($ <gexp-input> x)
+         (raise (condition (&gexp-input-error (input x)))))
         (x
          (return x)))))
 
diff --git a/tests/gexp.scm b/tests/gexp.scm
index 5c013d838d9bcca0bda4cdd84b805ba432b8b14c..50d09486599d94a5af234755255b94d8275cd47e 100644
--- a/tests/gexp.scm
+++ b/tests/gexp.scm
@@ -871,6 +871,13 @@ (define (matching-input drv output)
                    (eq? (derivation-input-derivation (lowered-gexp-guile lexp))
                         (%guile-for-build)))))))
 
+(test-eq "lower-gexp, non-self-quoting input"
+  +
+  (guard (c ((gexp-input-error? c)
+             (gexp-error-invalid-input c)))
+    (run-with-store %store
+      (lower-gexp #~(foo #$+)))))
+
 (test-assertm "gexp->derivation #:references-graphs"
   (mlet* %store-monad
       ((one (text-file "one" (random-text)))