diff --git a/sim/config.h.in b/sim/config.h.in
index 84c363c0aec..9a94b289e46 100644
--- a/sim/config.h.in
+++ b/sim/config.h.in
@@ -41,6 +41,9 @@
 /* Define to 1 if you have the `chmod' function. */
 #undef HAVE_CHMOD
 
+/* Is the prototype for getopt in <unistd.h> in the expected format? */
+#undef HAVE_DECL_GETOPT
+
 /* Define to 1 if you have the declaration of `tzname', and to 0 if you don't.
    */
 #undef HAVE_DECL_TZNAME
diff --git a/sim/configure b/sim/configure
index 75d1935df38..dac7f085be1 100755
--- a/sim/configure
+++ b/sim/configure
@@ -16428,6 +16428,38 @@ $as_echo "${WARN_CFLAGS} ${WERROR_CFLAGS}" >&6; }
 fi
 
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a known getopt prototype in unistd.h" >&5
+$as_echo_n "checking for a known getopt prototype in unistd.h... " >&6; }
+if ${sim_cv_decl_getopt_unistd_h+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <unistd.h>
+int
+main ()
+{
+extern int getopt (int, char *const*, const char *);
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  sim_cv_decl_getopt_unistd_h=yes
+else
+  sim_cv_decl_getopt_unistd_h=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $sim_cv_decl_getopt_unistd_h" >&5
+$as_echo "$sim_cv_decl_getopt_unistd_h" >&6; }
+if test $sim_cv_decl_getopt_unistd_h = yes; then
+
+$as_echo "#define HAVE_DECL_GETOPT 1" >>confdefs.h
+
+fi
+
 
 
 
diff --git a/sim/configure.ac b/sim/configure.ac
index 66a1020efe0..be0cfdbea32 100644
--- a/sim/configure.ac
+++ b/sim/configure.ac
@@ -177,6 +177,16 @@ SIM_AC_OPTION_STDIO
 SIM_AC_OPTION_TRACE
 SIM_AC_OPTION_WARNINGS
 
+AC_MSG_CHECKING(for a known getopt prototype in unistd.h)
+AC_CACHE_VAL(sim_cv_decl_getopt_unistd_h,
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <unistd.h>], [extern int getopt (int, char *const*, const char *);])],
+sim_cv_decl_getopt_unistd_h=yes, sim_cv_decl_getopt_unistd_h=no)])
+AC_MSG_RESULT($sim_cv_decl_getopt_unistd_h)
+if test $sim_cv_decl_getopt_unistd_h = yes; then
+  AC_DEFINE([HAVE_DECL_GETOPT], 1,
+	    [Is the prototype for getopt in <unistd.h> in the expected format?])
+fi
+
 dnl These are unfortunate.  They are conditionally called by other sim macros
 dnl but always used by common/Make-common.in.  So we have to subst here even
 dnl when the rest of the code is in the respective macros.  Once we merge the