[Bf-blender-cvs] [f7c8eb5cf5a] temp-node-error-messages: Add comment

[Hans Goudey]

Commit: f7c8eb5cf5afedbef82cda5a3206ddf03b50ec3f
Author: Hans Goudey
Date:   Tue Feb 2 20:25:00 2021 -0600
Branches: temp-node-error-messages
https://developer.blender.org/rBf7c8eb5cf5afedbef82cda5a3206ddf03b50ec3f

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===================================================================

M	source/blender/editors/space_node/node_draw.c

===================================================================

diff --git a/source/blender/editors/space_node/node_draw.c b/source/blender/editors/space_node/node_draw.c
index 176de793b67..0d00f35b1b0 100644
--- a/source/blender/editors/space_node/node_draw.c
+++ b/source/blender/editors/space_node/node_draw.c
@@ -1154,6 +1154,8 @@ static int node_add_error_message_button(bNodeTree *ntree,
   icon_offset -= NODE_HEADER_ICON_SIZE;
 
   UI_block_emboss_set(node->block, UI_EMBOSS_NONE);
+  /* The only reason to allocate this is that the ownership of
+   * #UI_but_func_tooltip_set's argument is transferred to the button. */
   NodeWarning *warning_alloc = MEM_mallocN(sizeof(NodeWarning), __func__);
   warning_alloc->type = message->type;
   warning_alloc->message = message->message;