diff --git a/gnu/packages/base.scm b/gnu/packages/base.scm
index 32bc69e2c4..5a3d5aced5 100644
--- a/gnu/packages/base.scm
+++ b/gnu/packages/base.scm
@@ -967,6 +967,10 @@ (define-public glibc
                      ;; library is empty by some criterion (such as their file
                      ;; size equaling eight bytes) rather than hardcoding them
                      ;; by name.
+
+                     ;; XXX: We forgot librt.a for the current version!  In
+                     ;; the meantime, gcc-toolchain provides it, but remove
+                     ;; that fix once librt.a is added here.
                      (define empty-static-libraries
                        '("libpthread.a" "libdl.a" "libutil.a" "libanl.a"))
                      (define (empty-static-library? file)
diff --git a/gnu/packages/commencement.scm b/gnu/packages/commencement.scm
index e522e70444..9604f06a47 100644
--- a/gnu/packages/commencement.scm
+++ b/gnu/packages/commencement.scm
@@ -3561,6 +3561,13 @@ (define* (make-gcc-toolchain gcc
                        (union-build (assoc-ref %outputs "static")
                                     (list (assoc-ref %build-inputs
                                                      "libc-static")))
+                       ;; XXX Remove once an empty librt.a is added to
+                       ;; libc:out.
+                       (copy-file
+                        (string-append (assoc-ref %outputs "out")
+                                       "/lib/libpthread.a")
+                        (string-append (assoc-ref %outputs "out")
+                                       "/lib/librt.a"))
                        #t))))
 
       (native-search-paths