Merge branch 'fix_test27_gcc' into 'master'

Check that an error is not created due to rounding with GCC 7.2.0.

Closes #400

See merge request !514

src/runner_doiact.h

@@ -1161,7 +1161,8 @@ void DOPAIR1_BRANCH(struct runner *r, struct cell *ci, struct cell *cj) {
                     p->x[1] * runner_shift[sid][1] +
                     p->x[2] * runner_shift[sid][2];
     if (fabsf(d - sort_i[pid].d) - ci->dx_max_sort >
-        1.0e-4 * max(fabsf(d), ci->dx_max_sort_old))
+            1.0e-4 * max(fabsf(d), ci->dx_max_sort_old) &&
+        fabsf(d - sort_i[pid].d) - ci->dx_max_sort > ci->width[0] * 1.0e-10)
       error(
           "particle shift diff exceeds dx_max_sort in cell ci. ci->nodeID=%d "
           "cj->nodeID=%d d=%e sort_i[pid].d=%e ci->dx_max_sort=%e "
@@ -1174,8 +1175,9 @@ void DOPAIR1_BRANCH(struct runner *r, struct cell *ci, struct cell *cj) {
     const float d = p->x[0] * runner_shift[sid][0] +
                     p->x[1] * runner_shift[sid][1] +
                     p->x[2] * runner_shift[sid][2];
-    if (fabsf(d - sort_j[pjd].d) - cj->dx_max_sort >
-        1.0e-4 * max(fabsf(d), cj->dx_max_sort_old))
+    if ((fabsf(d - sort_j[pjd].d) - cj->dx_max_sort) >
+            1.0e-4 * max(fabsf(d), cj->dx_max_sort_old) &&
+        (fabsf(d - sort_j[pjd].d) - cj->dx_max_sort) > cj->width[0] * 1.0e-10)
       error(
           "particle shift diff exceeds dx_max_sort in cell cj. cj->nodeID=%d "
           "ci->nodeID=%d d=%e sort_j[pjd].d=%e cj->dx_max_sort=%e "
@@ -1672,7 +1674,8 @@ void DOPAIR2_BRANCH(struct runner *r, struct cell *ci, struct cell *cj) {
                     p->x[1] * runner_shift[sid][1] +
                     p->x[2] * runner_shift[sid][2];
     if (fabsf(d - sort_i[pid].d) - ci->dx_max_sort >
-        1.0e-4 * max(fabsf(d), ci->dx_max_sort_old))
+            1.0e-4 * max(fabsf(d), ci->dx_max_sort_old) &&
+        fabsf(d - sort_i[pid].d) - ci->dx_max_sort > ci->width[0] * 1.0e-10)
       error(
           "particle shift diff exceeds dx_max_sort in cell ci. ci->nodeID=%d "
           "cj->nodeID=%d d=%e sort_i[pid].d=%e ci->dx_max_sort=%e "
@@ -1686,7 +1689,8 @@ void DOPAIR2_BRANCH(struct runner *r, struct cell *ci, struct cell *cj) {
                     p->x[1] * runner_shift[sid][1] +
                     p->x[2] * runner_shift[sid][2];
     if (fabsf(d - sort_j[pjd].d) - cj->dx_max_sort >
-        1.0e-4 * max(fabsf(d), cj->dx_max_sort_old))
+            1.0e-4 * max(fabsf(d), cj->dx_max_sort_old) &&
+        fabsf(d - sort_j[pjd].d) - cj->dx_max_sort > cj->width[0] * 1.0e-10)
       error(
           "particle shift diff exceeds dx_max_sort in cell cj. cj->nodeID=%d "
           "ci->nodeID=%d d=%e sort_j[pjd].d=%e cj->dx_max_sort=%e "

tests/tolerance_27_perturbed_h2.dat

 #   ID      pos_x      pos_y      pos_z        v_x        v_y        v_z           rho        rho_dh        wcount     wcount_dh         div_v       curl_vx       curl_vy       curl_vz
     0	      1e-6       1e-6	      1e-6 	       1e-6 	    1e-6	     1e-6	         3e-6       1e-4	        5e-4       1.5e-2		         1.4e-5	       3e-6	         3e-6		       1e-5
-    0	      1e-6       1e-6	      1e-6 	       1e-6 	    1e-6	     1e-6	         1.5e-6	    2.5e-2	      1e-5       5.86e-3		       4.96e-4	     3e-3	         4.5e-3	 	       3e-3
+    0	      1e-6       1e-6	      1e-6 	       1e-6 	    1e-6	     1e-6	         1.5e-6	    2.5e-2	      1e-5       5.86e-3		       1.17e-3	     3e-3	         5.65e-3	 	       3e-3
     0	      1e-6       1e-6	      1e-6 	       1e-6 	    1e-6	     1e-6	         1e-6	      1e-6	        1e-6       1e0		           1e-6	         4e-6	         4e-6		       4e-6