1 files changed, 24 insertions, 22 deletions

diff --git a/lib/http2.c b/lib/http2.c
index e123bc56c..f8e23c517 100644
--- a/lib/http2.c
+++ b/lib/http2.c
@@ -2137,35 +2137,37 @@ CURLcode Curl_http2_switched(struct connectdata *conn,
 void Curl_http2_add_child(struct Curl_easy *parent, struct Curl_easy *child,
                           bool exclusive)
 {
-  struct Curl_http2_dep **tail;
-  struct Curl_http2_dep *dep = calloc(1, sizeof(struct Curl_http2_dep));
-  dep->data = child;
-
-  if(parent->set.stream_dependents && exclusive) {
-    struct Curl_http2_dep *node = parent->set.stream_dependents;
-    while(node) {
-      node->data->set.stream_depends_on = child;
-      node = node->next;
+  if(parent) {
+    struct Curl_http2_dep **tail;
+    struct Curl_http2_dep *dep = calloc(1, sizeof(struct Curl_http2_dep));
+    dep->data = child;
+
+    if(parent->set.stream_dependents && exclusive) {
+      struct Curl_http2_dep *node = parent->set.stream_dependents;
+      while(node) {
+        node->data->set.stream_depends_on = child;
+        node = node->next;
+      }
+
+      tail = &child->set.stream_dependents;
+      while(*tail)
+        tail = &(*tail)->next;
+
+      DEBUGASSERT(!*tail);
+      *tail = parent->set.stream_dependents;
+      parent->set.stream_dependents = 0;
     }
 
-    tail = &child->set.stream_dependents;
-    while(*tail)
+    tail = &parent->set.stream_dependents;
+    while(*tail) {
+      (*tail)->data->set.stream_depends_e = FALSE;
       tail = &(*tail)->next;
+    }
 
     DEBUGASSERT(!*tail);
-    *tail = parent->set.stream_dependents;
-    parent->set.stream_dependents = 0;
+    *tail = dep;
   }
 
-  tail = &parent->set.stream_dependents;
-  while(*tail) {
-    (*tail)->data->set.stream_depends_e = FALSE;
-    tail = &(*tail)->next;
-  }
-
-  DEBUGASSERT(!*tail);
-  *tail = dep;
-
   child->set.stream_depends_on = parent;
   child->set.stream_depends_e = exclusive;
 }