diff --git a/lib/System/Unix/Program.inc b/lib/System/Unix/Program.inc
index e8c28062478..c10498a375a 100644
--- a/lib/System/Unix/Program.inc
+++ b/lib/System/Unix/Program.inc
@@ -126,7 +126,7 @@ static void TimeOutHandler(int Sig) {
 
 static void SetMemoryLimits (unsigned size)
 {
-#if HAVE_SYS_RESOURCE_H
+#if HAVE_SYS_RESOURCE_H && HAVE_GETRLIMIT && HAVE_SETRLIMIT
   struct rlimit r;
   __typeof__ (r.rlim_cur) limit = (__typeof__ (r.rlim_cur)) (size) * 1048576;
 
diff --git a/lib/System/Unix/Signals.inc b/lib/System/Unix/Signals.inc
index 676e1e5356c..7bd752649a4 100644
--- a/lib/System/Unix/Signals.inc
+++ b/lib/System/Unix/Signals.inc
@@ -52,7 +52,16 @@ static const int *const IntSigsEnd =
 // KillSigs - Signals that are synchronous with the program that will cause it
 // to die.
 static const int KillSigs[] = {
-  SIGILL, SIGTRAP, SIGABRT, SIGFPE, SIGBUS, SIGSEGV, SIGSYS, SIGXCPU, SIGXFSZ
+  SIGILL, SIGTRAP, SIGABRT, SIGFPE, SIGBUS, SIGSEGV
+#ifdef SIGSYS
+  , SIGSYS
+#endif
+#ifdef SIGXCPU
+  , SIGXCPU
+#endif
+#ifdef SIGEMT
+  , SIGXFSZ
+#endif
 #ifdef SIGEMT
   , SIGEMT
 #endif