https://gitlab.inria.fr/mpc/mpc/-/commit/e944aa454e60cbff8ab4e8c70dd974083398378f
https://sympa.inria.fr/sympa/arc/mpc-discuss/2022-12/msg00034.html

From e944aa454e60cbff8ab4e8c70dd974083398378f Mon Sep 17 00:00:00 2001
From: Paul Zimmermann <Paul.Zimmermann@inria.fr>
Date: Sat, 10 Dec 2022 08:47:51 +0100
Subject: [PATCH] functions with FILE arguments should be defined only when
 stdio.h is included

--- a/src/mpc.h
+++ b/src/mpc.h
@@ -270,6 +270,7 @@ __MPC_DECLSPEC long double _Complex mpc_get_ldc (mpc_srcptr, mpc_rnd_t);
 __MPC_DECLSPEC int mpc_inp_str    (mpc_ptr, FILE *, size_t *, int, mpc_rnd_t);
 __MPC_DECLSPEC size_t mpc_out_str (FILE *, int, size_t, mpc_srcptr, mpc_rnd_t);
 __MPC_DECLSPEC void mpcb_out_str  (FILE *f, mpcb_srcptr);
+__MPC_DECLSPEC void mpcr_out_str (FILE *f, mpcr_srcptr r);
 #endif
 
 __MPC_DECLSPEC int mpcr_inf_p (mpcr_srcptr r);
@@ -284,7 +285,6 @@ __MPC_DECLSPEC void mpcr_set_ui64_2si64 (mpcr_ptr r, uint64_t mant,
    int64_t exp);
 __MPC_DECLSPEC void mpcr_max (mpcr_ptr r, mpcr_srcptr s, mpcr_srcptr t);
 __MPC_DECLSPEC int64_t mpcr_get_exp (mpcr_srcptr r);
-__MPC_DECLSPEC void mpcr_out_str (FILE *f, mpcr_srcptr r);
 __MPC_DECLSPEC void mpcr_mul (mpcr_ptr r, mpcr_srcptr s, mpcr_srcptr t);
 __MPC_DECLSPEC void mpcr_mul_2ui (mpcr_ptr r, mpcr_srcptr s,
    unsigned long int e);
-- 
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