Fix nsga2 bug (#438)

* fix allocation bugs for 64 bit systems

* enable flaky nsga2 test

* ensure array access is not out of bounds

* run tests in isolation

* enforce popsize in increments of 4

* flake8

---------

Co-authored-by: Eirikur Jonsson <[email protected]>
Co-authored-by: Marco Mangano <[email protected]>

Author: 3 people

.github/test_real.sh

@@ -11,4 +11,4 @@ cd tests
 # we have to copy over the coveragerc file to make sure it's in the
 # same directory where codecov is run
 cp ../.coveragerc .
-testflo --pre_announce --disallow_deprecations -v --coverage --coverpkg pyoptsparse $EXTRA_FLAGS
+testflo -i --pre_announce --disallow_deprecations -v --coverage --coverpkg pyoptsparse $EXTRA_FLAGS

.github/workflows/linux-build.yml

@@ -31,4 +31,4 @@ jobs:
       - name: Run tests
         run: |
           cd tests
-          testflo --pre_announce -v -n 1 .
+          testflo -i --pre_announce -v -n 1 .

.github/workflows/windows-build.yml

@@ -52,4 +52,4 @@ jobs:
         run: |
           conda activate pyos-build
           cd tests
-          testflo --pre_announce -v -n 1 .
+          testflo -i --pre_announce -v -n 1 .

pyoptsparse/pyNSGA2/pyNSGA2.py

@@ -34,6 +34,9 @@ def __init__(self, raiseError=True, options={}):
         if isinstance(nsga2, str) and raiseError:
             raise ImportError(nsga2)
 
+        if self.getOption("PopSize") % 4 != 0:
+            raise ValueError("Option 'PopSize' must be a multiple of 4")
+
     @staticmethod
     def _getInforms():
         informs = {}

pyoptsparse/pyNSGA2/source/allocate.c

@@ -30,7 +30,7 @@ void allocate_memory_ind (individual *ind, Global global)
     if (global.nbin != 0)
     {
         ind->xbin = (double *)malloc(global.nbin*sizeof(double));
-        ind->gene = (int **)malloc(global.nbin*sizeof(int));
+        ind->gene = (int **)malloc(global.nbin*sizeof(int *));
         for (j=0; j<global.nbin; j++)
         {
             ind->gene[j] = (int *)malloc(global.nbits[j]*sizeof(int));

pyoptsparse/pyNSGA2/source/crowddist.c

@@ -26,7 +26,7 @@ void assign_crowding_distance_list (population *pop, list *lst, int front_size,
         pop->ind[lst->child->index].crowd_dist = INF;
         return;
     }
-    obj_array = (int **)malloc(global.nobj*sizeof(int));
+    obj_array = (int **)malloc(global.nobj*sizeof(int *));
     dist = (int *)malloc(front_size*sizeof(int));
     for (i=0; i<global.nobj; i++)
     {
@@ -66,7 +66,7 @@ void assign_crowding_distance_indices (population *pop, int c1, int c2, Global g
         pop->ind[c2].crowd_dist = INF;
         return;
     }
-    obj_array = (int **)malloc(global.nobj*sizeof(int));
+    obj_array = (int **)malloc(global.nobj*sizeof(int *));
     dist = (int *)malloc(front_size*sizeof(int));
     for (i=0; i<global.nobj; i++)
     {

tests/test_nsga2_multi_objective.py

@@ -52,7 +52,7 @@ def setup_optProb(self, n_obj):
     @parameterized.expand(
         [
             (1,),
-            # (2,), # skipping flaky multi-objective test
+            (2,),
         ]
     )
     def test_opt(self, n_obj):
@@ -73,6 +73,13 @@ def test_opt(self, n_obj):
             assert_allclose(sol.fStar["obj1"], 12.0, atol=tol, rtol=tol)
             assert_allclose(sol.fStar["obj2"], 0.0, atol=tol, rtol=tol)
 
+    def test_options(self):
+        with self.assertRaises(ValueError):
+            # PopSize must be a multiple of 4
+            self.setup_optProb(1)
+            optOptions = {"PopSize": 5}
+            self.optimize(optOptions=optOptions)
+
 
 if __name__ == "__main__":
     unittest.main()