diff --git a/src/config.h.in b/src/config.h.in
index 1b01633..9657556 100644
--- a/src/config.h.in
+++ b/src/config.h.in
@@ -497,6 +497,9 @@
 /* Define to inline symbol or empty */
 #undef inline
 
+/* Define if _SC_SIGSTKSZ is available via sysconf() */
+#undef HAVE_SYSCONF_SIGSTKSZ
+
 /* Do we need FIPS warning? */
 #undef HAVE_FIPS_WARNING
 
diff --git a/src/configure.ac b/src/configure.ac
index aba4e1b..8a14a55 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -4137,6 +4137,15 @@ AC_TRY_COMPILE(
 	AC_MSG_RESULT(yes); AC_DEFINE(HAVE_SYSCONF),
 	AC_MSG_RESULT(not usable))
 
+dnl check if we have _SC_SIGSTKSZ via sysconf()
+AC_MSG_CHECKING(for _SC_SIGSTKSZ via sysconf())
+AC_TRY_COMPILE(
+[#include <unistd.h>],
+[	(void)sysconf(_SC_SIGSTKSZ);
+	],
+	AC_MSG_RESULT(yes); AC_DEFINE(HAVE_SYSCONF_SIGSTKSZ),
+	AC_MSG_RESULT(not usable))
+
 AC_CHECK_SIZEOF([int])
 AC_CHECK_SIZEOF([long])
 AC_CHECK_SIZEOF([time_t])
diff --git a/src/os_unix.c b/src/os_unix.c
index 1edc7e6..fe12aba 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -783,7 +783,7 @@ mch_stackcheck(char *p)
  * completely full.
  */
 
-#ifndef SIGSTKSZ
+#if !defined SIGSTKSZ && !defined(HAVE_SYSCONF_SIGSTKSZ)
 # define SIGSTKSZ 8000    // just a guess of how much stack is needed...
 #endif
 
@@ -806,13 +806,21 @@ init_signal_stack(void)
 #  else
 	sigstk.ss_sp = signal_stack;
 #  endif
+#  ifdef HAVE_SYSCONF_SIGSTKSZ
+	sigstk.ss_size = sysconf(_SC_SIGSTKSZ);
+#  else
 	sigstk.ss_size = SIGSTKSZ;
+#  endif
 	sigstk.ss_flags = 0;
 	(void)sigaltstack(&sigstk, NULL);
 # else
 	sigstk.ss_sp = signal_stack;
 	if (stack_grows_downwards)
+#  ifdef HAVE_SYSCONF_SIGSTKSZ
+	    sigstk.ss_sp += sysconf(_SC_SIGSTKSZ) - 1;
+#  else
 	    sigstk.ss_sp += SIGSTKSZ - 1;
+#  endif
 	sigstk.ss_onstack = 0;
 	(void)sigstack(&sigstk, NULL);
 # endif
@@ -3261,7 +3269,11 @@ mch_early_init(void)
      * Ignore any errors.
      */
 #if defined(HAVE_SIGALTSTACK) || defined(HAVE_SIGSTACK)
+# ifdef HAVE_SYSCONF_SIGSTKSZ
+    signal_stack = alloc(sysconf(_SC_SIGSTKSZ));
+# else
     signal_stack = alloc(SIGSTKSZ);
+# endif
     init_signal_stack();
 #endif
 }