diff --git a/guix/build/texlive-build-system.scm b/guix/build/texlive-build-system.scm
index 1c393ecd9d..a7cb8dd1ad 100644
--- a/guix/build/texlive-build-system.scm
+++ b/guix/build/texlive-build-system.scm
@@ -60,7 +60,12 @@ (define* (configure #:key inputs #:allow-other-keys)
       (("^TEXMF = .*")
        "TEXMF = $TEXMFROOT/share/texmf-dist\n"))
     (setenv "TEXMFCNF" (dirname texmf.cnf))
-    (setenv "TEXMF" (string-append out "/share/texmf-dist")))
+    (setenv "TEXMF" (string-append out "/share/texmf-dist"))
+
+    ;; Don't truncate lines.
+    (setenv "error_line" "254") ; must be less than 255
+    (setenv "half_error_line" "238") ; must be less than error_line - 15
+    (setenv "max_print_line" "1000"))
   (mkdir "build")
   #t)