do not produce test goals for constructor and destructor methods

Signed-off-by: Lucas Cordeiro <lucasccordeiro@gmail.com>

Author: lucasccordeiro

regression/cbmc-cover/consider_goals1/test.desc

@@ -3,6 +3,6 @@ if_icmp1.class
 --cover location --no-trivial-tests
 ^EXIT=0$
 ^SIGNAL=0$
-^\*\* 13 of 29 covered (44.8%)
+^\*\* 12 of 27 covered (44.4%)
 --
 ^warning: ignoring

regression/cbmc-cover/consider_goals2/test.desc

@@ -3,6 +3,6 @@ Person.class
 --cover location --no-trivial-tests
 ^EXIT=0$
 ^SIGNAL=0$
-^\*\* 5 of 5 covered (100.0%)
+^\*\* 4 of 4 covered (100.0%)
 --
 ^warning: ignoring

regression/cbmc-cover/consider_goals3/test.desc

@@ -3,6 +3,6 @@ Person.class
 --cover location --no-trivial-tests
 ^EXIT=0$
 ^SIGNAL=0$
-^\*\* 12 of 15 covered (80.0%)
+^\*\* 11 of 14 covered (78.6%)
 --
 ^warning: ignoring

regression/cbmc-cover/consider_goals4/test.desc

@@ -3,6 +3,6 @@ Person.class
 --cover location --no-trivial-tests
 ^EXIT=0$
 ^SIGNAL=0$
-^\*\* 15 of 23 covered (65.2%)
+^\*\* 14 of 22 covered (63.6%)
 --
 ^warning: ignoring

regression/cbmc-cover/consider_goals5/test.desc

@@ -3,6 +3,6 @@ Person.class
 --cover location --no-trivial-tests
 ^EXIT=0$
 ^SIGNAL=0$
-^\*\* 16 of 24 covered (66.7%)
+^\*\* 15 of 23 covered (65.2%)
 --
 ^warning: ignoring

regression/cbmc-cover/consider_goals6/test.desc

@@ -3,6 +3,6 @@ Account.class
 --cover location --no-trivial-tests
 ^EXIT=0$
 ^SIGNAL=0$
-^\*\* 17 of 18 covered (94.4%)
+^\*\* 13 of 13 covered (100.0%)
 --
 ^warning: ignoring

src/goto-instrument/cover.cpp

@@ -8,6 +8,8 @@ Date: May 2016
 
 \*******************************************************************/
 
+#include <iostream>
+
 #include <algorithm>
 #include <iterator>
 
@@ -1608,9 +1610,12 @@ bool consider_goals(
       ++count_decl;
   }
 
-  //this might be a get or set method (pattern)
-  result = !((count_decl==0) && (count_goto<=1) &&
-		   (count_assignments>0 && count_assignments<5));
+  //check whether this is a constructor/destructor or a get/set (pattern)
+  if (!count_goto && !count_assignments && !count_decl)
+    result=false;
+  else
+    result = !((count_decl==0) && (count_goto<=1) &&
+		     (count_assignments>0 && count_assignments<5));
 
   return result;
 }