3 files changed, 49 insertions, 5 deletions

diff --git a/source/blender/modifiers/intern/MOD_fluid.c b/source/blender/modifiers/intern/MOD_fluid.c
index a14d582063a..e087b8411f8 100644
--- a/source/blender/modifiers/intern/MOD_fluid.c
+++ b/source/blender/modifiers/intern/MOD_fluid.c
@@ -25,6 +25,7 @@
 
 #include "MEM_guardedalloc.h"
 
+#include "BLI_task.h"
 #include "BLI_utildefines.h"
 
 #include "BLT_translation.h"
@@ -112,6 +113,31 @@ static void requiredDataMask(Object *UNUSED(ob),
   }
 }
 
+typedef struct FluidIsolationData {
+  Depsgraph *depsgraph;
+  Object *object;
+  Mesh *mesh;
+  FluidModifierData *fmd;
+
+  Mesh *result;
+} FluidIsolationData;
+
+#ifdef WITH_FLUID
+static void fluid_modifier_do_isolated(void *userdata)
+{
+  FluidIsolationData *isolation_data = (FluidIsolationData *)userdata;
+
+  Scene *scene = DEG_get_evaluated_scene(isolation_data->depsgraph);
+
+  Mesh *result = BKE_fluid_modifier_do(isolation_data->fmd,
+                                       isolation_data->depsgraph,
+                                       scene,
+                                       isolation_data->object,
+                                       isolation_data->mesh);
+  isolation_data->result = result ? result : isolation_data->mesh;
+}
+#endif /* WITH_FLUID */
+
 static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *ctx, Mesh *me)
 {
 #ifndef WITH_FLUID
@@ -119,16 +145,24 @@ static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *ctx, Mesh *
   return me;
 #else
   FluidModifierData *fmd = (FluidModifierData *)md;
-  Mesh *result = NULL;
 
   if (ctx->flag & MOD_APPLY_ORCO) {
     return me;
   }
 
-  Scene *scene = DEG_get_evaluated_scene(ctx->depsgraph);
-
-  result = BKE_fluid_modifier_do(fmd, ctx->depsgraph, scene, ctx->object, me);
-  return result ? result : me;
+  /* Isolate execution of Mantaflow when running from dependency graph. The reason for this is
+   * because Mantaflow uses TBB to parallel its own computation which without isolation will start
+   * stealing tasks from dependency graph. Stealing tasks from the dependency graph might cause
+   * a recursive lock when Python drivers are used (because Mantaflow is interfaced via Python as
+   * well. */
+  FluidIsolationData isolation_data;
+  isolation_data.depsgraph = ctx->depsgraph;
+  isolation_data.object = ctx->object;
+  isolation_data.mesh = me;
+  isolation_data.fmd = fmd;
+  BLI_task_isolate(fluid_modifier_do_isolated, &isolation_data);
+
+  return isolation_data.result;
 #endif /* WITH_FLUID */
 }
 
diff --git a/source/blender/modifiers/intern/MOD_nodes.cc b/source/blender/modifiers/intern/MOD_nodes.cc
index e6cc7663c58..c88940c00c2 100644
--- a/source/blender/modifiers/intern/MOD_nodes.cc
+++ b/source/blender/modifiers/intern/MOD_nodes.cc
@@ -917,6 +917,10 @@ static void store_output_value_in_geometry(GeometrySet &geometry_set,
     CurveComponent &component = geometry_set.get_component_for_write<CurveComponent>();
     store_field_on_geometry_component(component, attribute_name, domain, field);
   }
+  if (geometry_set.has_instances()) {
+    InstancesComponent &component = geometry_set.get_component_for_write<InstancesComponent>();
+    store_field_on_geometry_component(component, attribute_name, domain, field);
+  }
 }
 
 /**
@@ -1424,13 +1428,18 @@ static void output_attribute_panel_draw(const bContext *UNUSED(C), Panel *panel)
   uiLayoutSetPropSep(layout, true);
   uiLayoutSetPropDecorate(layout, true);
 
+  bool has_output_attribute = false;
   if (nmd->node_group != nullptr && nmd->settings.properties != nullptr) {
     LISTBASE_FOREACH (bNodeSocket *, socket, &nmd->node_group->outputs) {
       if (socket_type_has_attribute_toggle(*socket)) {
+        has_output_attribute = true;
         draw_property_for_output_socket(layout, *nmd, ptr, *socket);
       }
     }
   }
+  if (!has_output_attribute) {
+    uiItemL(layout, IFACE_("No group output attributes connected."), ICON_INFO);
+  }
 }
 
 static void panelRegister(ARegionType *region_type)
diff --git a/source/blender/modifiers/intern/MOD_nodes_evaluator.cc b/source/blender/modifiers/intern/MOD_nodes_evaluator.cc
index 69132f6c177..a312872f5d9 100644
--- a/source/blender/modifiers/intern/MOD_nodes_evaluator.cc
+++ b/source/blender/modifiers/intern/MOD_nodes_evaluator.cc
@@ -1455,6 +1455,7 @@ class GeometryNodesEvaluator {
     }
     void *converted_buffer = allocator.allocate(required_type.size(), required_type.alignment());
     this->convert_value(type, required_type, buffer, converted_buffer);
+    type.destruct(buffer);
     return {required_type, converted_buffer};
   }