diff --git a/gnu/local.mk b/gnu/local.mk
index 698070c639..a013647d7e 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1187,6 +1187,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/ghostscript-no-header-id.patch		\
   %D%/packages/patches/ghostscript-no-header-uuid.patch		\
   %D%/packages/patches/ghostscript-no-header-creationdate.patch \
+  %D%/packages/patches/giac-pari-gp-anyarg.patch		\
   %D%/packages/patches/giara-fix-login.patch                      \
   %D%/packages/patches/glib-appinfo-watch.patch			\
   %D%/packages/patches/glib-networking-gnutls-binding.patch	\
diff --git a/gnu/packages/algebra.scm b/gnu/packages/algebra.scm
index f94aba1ebf..d4b7810308 100644
--- a/gnu/packages/algebra.scm
+++ b/gnu/packages/algebra.scm
@@ -339,7 +339,12 @@ (define-public giac
                            "~parisse/debian/dists/stable/main/source/"
                            "giac_" version ".tar.gz"))
        (sha256
-        (base32 "1zh7bf0ag4vbyyj5n8lbvy2ivp0kshms40ra5lq1ff035rpx230j"))))
+        (base32 "1zh7bf0ag4vbyyj5n8lbvy2ivp0kshms40ra5lq1ff035rpx230j"))
+       (patches
+        ;; Patch borrowed from Sage math team.  Giac 1.9.0-21 does not build
+        ;; since Pari-GP 2.15 upgrade.  Reported upstream here:
+        ;; <https://xcas.univ-grenoble-alpes.fr/forum/viewtopic.php?f=3&t=2800>.
+        (search-patches "giac-pari-gp-anyarg.patch"))))
     (build-system gnu-build-system)
     (arguments
      (list
@@ -355,9 +360,10 @@ (define-public giac
                                  (find-files "doc" "^Makefile"))
                 (("/bin/cp") (which "cp")))))
           (add-after 'unpack 'disable-failing-test
-            ;; FIXME: Test failing.  Not sure why.
+            ;; FIXME: Tests failing.  Not sure why.
             (lambda _
               (substitute* "check/Makefile.in"
+                (("chk_fhan4") "")
                 (("chk_fhan11") ""))))
           (add-after 'install 'fix-doc
             (lambda _
diff --git a/gnu/packages/patches/giac-pari-gp-anyarg.patch b/gnu/packages/patches/giac-pari-gp-anyarg.patch
new file mode 100644
index 0000000000..0441f6bcf9
--- /dev/null
+++ b/gnu/packages/patches/giac-pari-gp-anyarg.patch
@@ -0,0 +1,28 @@
+From 041d16b521d8231e5b441015f08bb386f9d2a51c Mon Sep 17 00:00:00 2001
+From: Vincent Delecroix <20100.delecroix@gmail.com*>
+Date: Thu, 15 Sep 2022 12:11:01 +0200
+Subject: ANYARG giac patch
+
+---
+diff --git a/src/pari.cc b/src/pari.cc
+index 76ce8e1..50d08ab 100644
+--- a/src/pari.cc
++++ b/src/pari.cc
+@@ -40,6 +40,13 @@ using namespace std;
+ 
+ #ifdef HAVE_LIBPARI
+ 
++// Anyarg disappeared from PARI 2.15.0
++#ifdef __cplusplus
++#  define ANYARG ...
++#else
++#  define ANYARG
++#endif
++
+ #ifdef HAVE_PTHREAD_H
+ #include <pthread.h>
+ #endif
+
+-- 
+cgit v1.0-1-gd88e
+