SPDX-License-Identifier: GPL-3.0-or-later

Fix MPFR callback pointer prototype for modern compilers.

--- gawk-4.2.1/mpfr.c
+++ gawk-4.2.1/mpfr.c
@@ -689,7 +689,7 @@
 
 static inline NODE *
 do_mpfr_func(const char *name,
-		int (*mpfr_func)(),	/* putting argument types just gets the compiler confused */
+		int (*mpfr_func)(mpfr_ptr, mpfr_srcptr, mpfr_rnd_t),
 		int nargs)
 {
 	NODE *t1, *res;