diff --git a/backport-0001-added-missing-include.patch b/backport-0001-added-missing-include.patch
new file mode 100644
index 0000000000000000000000000000000000000000..765d012413d91dfd1c4ff535b6de7102d8e89372
--- /dev/null
+++ b/backport-0001-added-missing-include.patch
@@ -0,0 +1,31 @@
+From 21668770977368459c74723f2bddad38b727ea20 Mon Sep 17 00:00:00 2001
+From: Paul Zimmermann <Paul.Zimmermann@inria.fr>
+Date: Thu, 20 Aug 2020 08:56:54 +0200
+Subject: [PATCH 07/11] added missing include
+
+Reported by Andreas, while using mpc-1.2.0 to bootstrap Guix,
+where mpc-1.2.0 is used to compile gcc-7.5.0:
+
+In file included from ../../../gcc-7.5.0/mpc/src/asin.c:22:0:
+../../../gcc-7.5.0/mpc/src/asin.c: In function 'mpc_asin_series':
+../../../gcc-7.5.0/mpc/src/asin.c:132:27: error: 'ULONG_MAX' undeclared (first use in this function)
+   MPC_ASSERT(2 * k - 1 <= ULONG_MAX / (2 * k - 1));
+---
+ src/asin.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/src/asin.c b/src/asin.c
+index 444275f..2c3fa32 100644
+--- a/src/asin.c
++++ b/src/asin.c
+@@ -19,6 +19,7 @@ along with this program. If not, see http://www.gnu.org/licenses/ .
+ */
+ 
+ #include <stdio.h>
++#include <limits.h> /* for ULONG_MAX */
+ #include "mpc-impl.h"
+ 
+ /* Special case op = 1 + i*y for tiny y (see algorithms.tex).
+-- 
+1.8.3.1
+
diff --git a/libmpc.spec b/libmpc.spec
index ac22ec0c794f79cd4a9b1c30b569be46f89db8dd..4b8388de3c82ca5ff479c1fb6d4cd3868b0b7561 100644
--- a/libmpc.spec
+++ b/libmpc.spec
@@ -1,6 +1,6 @@
 Name: libmpc
 Version: 1.2.0
-Release: 1
+Release: 2
 Summary: C library for multiple precision complex arithmetic
 License: LGPLv3+ and GFDL
 URL: http://www.multiprecision.org/
@@ -18,6 +18,8 @@ same principles as MPFR.
 
 %package devel
 Summary: Header and shared development libraries for MPC
+Patch6000: backport-0001-added-missing-include.patch
+
 Requires: %{name}%{?_isa} = %{version}-%{release}
 Requires: mpfr-devel gmp-devel
 
@@ -26,6 +28,7 @@ Header files and shared object symlinks for MPC is a C library.
 
 %prep
 %setup -q -n mpc-%{version}
+%patch6000 -p1
 
 %build
 %configure --disable-static
@@ -68,6 +71,8 @@ fi
 %{_libdir}/libmpc.so
 
 %changelog
+* Thu Sep 24 2020 EulerOSWander<314264452@qq.com> - 1.2.0-2
+- added missing include.
 * Sat Aug 22 2020 Yunfeng Ye<yeyunfeng@huawei.com> - 1.2.0-1
 - Upgrade to 1.2.0