test: add fp-reachability test 3

This test tests whether paths are cut off in case a combination of
functions is specified which is not on the same path. As there does
not exist a single execution path with both functions b and c, all
functions should be removed.

Author: nmanthey

regression/goto-instrument/fp-reachability-slice3/main.c

@@ -0,0 +1,34 @@
+void a()
+{
+  int e;
+}
+
+void b()
+{
+  double f;
+  if(f == 0)
+    a();
+}
+
+void c()
+{
+  int d;
+}
+
+int main()
+{
+  int k;
+  if(k == 0)
+  {
+    int l;
+    a();
+    c();
+  }
+  else
+  {
+    b();
+  }
+  int n;
+  a();
+  return n;
+}

regression/goto-instrument/fp-reachability-slice3/test.desc

@@ -0,0 +1,10 @@
+CORE
+main.c
+--fp-reachability-slice c
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring
+dead d;
+dead e;
+dead f;