teams: preallocate num_contexts if config_mask set

src/shmem_team.c

@@ -336,21 +336,27 @@ int shmem_internal_team_split_strided(shmem_internal_team_t *parent_team, int PE
         myteam->size        = PE_size;
 
         if (config_mask == 0) {
-            shmem_team_config_t default_config;
-            default_config.num_contexts = 0;
-            myteam->config_mask = 0;
-            memcpy(&myteam->config, &default_config, sizeof(shmem_team_config_t));
+            shmem_team_config_t defaults;
+            myteam->config_mask   = 0;
+            myteam->contexts_len  = 0;
+            defaults.num_contexts = 0;
+            memcpy(&myteam->config, &defaults, sizeof(shmem_team_config_t));
         } else {
             if (config_mask != SHMEM_TEAM_NUM_CONTEXTS) {
                 RAISE_WARN_MSG("Invalid team_split_strided config_mask (%ld)\n", config_mask);
                 return -1;
             } else {
-                myteam->config      = *config;
-                myteam->config_mask = config_mask;
+                shmem_internal_assertp(config->num_contexts >= 0);
+                myteam->config       = *config;
+                myteam->config_mask  = config_mask;
+                myteam->contexts_len = config->num_contexts;
+                myteam->contexts     = malloc(config->num_contexts * sizeof(shmem_transport_ctx_t*));
+                for (int i = 0; i < config->num_contexts; i++) {
+                    myteam->contexts[i] = NULL;
+                }
             }
         }
 
-        myteam->contexts_len = 0;
         myteam->psync_idx = -1;
 
         shmem_internal_op_to_all(psync_pool_avail_reduced,