3 files changed, 5 insertions, 5 deletions
diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 3a38a14cdd..31d44c68bf 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -1903,7 +1903,7 @@ Integer nvim_buf_add_highlight(Buffer buffer, Integer ns_id, String hl_group, In
 
   int hl_id = 0;
   if (hl_group.size > 0) {
-    hl_id = syn_check_group((char_u *)hl_group.data, (int)hl_group.size);
+    hl_id = syn_check_group(hl_group.data, (int)hl_group.size);
   } else {
     return ns_id;
   }
diff --git a/src/nvim/api/private/helpers.c b/src/nvim/api/private/helpers.c
index aed87048ce..b2529db5be 100644
--- a/src/nvim/api/private/helpers.c
+++ b/src/nvim/api/private/helpers.c
@@ -1559,7 +1559,7 @@ int object_to_hl_id(Object obj, const char *what, Error *err)
 {
   if (obj.type == kObjectTypeString) {
     String str = obj.data.string;
-    return str.size ? syn_check_group((char_u *)str.data, (int)str.size) : 0;
+    return str.size ? syn_check_group(str.data, (int)str.size) : 0;
   } else if (obj.type == kObjectTypeInteger) {
     return MAX((int)obj.data.integer, 0);
   } else {
@@ -1593,7 +1593,7 @@ HlMessage parse_hl_msg(Array chunks, Error *err)
       String hl = chunk.items[1].data.string;
       if (hl.size > 0) {
         // TODO(bfredl): use object_to_hl_id and allow integer
-        int hl_id = syn_check_group((char_u *)hl.data, (int)hl.size);
+        int hl_id = syn_check_group(hl.data, (int)hl.size);
         attr = hl_id > 0 ? syn_id2attr(hl_id) : 0;
       }
     }
diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index 0565f8cd77..e58a59e872 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -195,7 +195,7 @@ Dictionary nvim_get_hl_by_id(Integer hl_id, Boolean rgb, Error *err)
 Integer nvim_get_hl_id_by_name(String name)
   FUNC_API_SINCE(7)
 {
-  return syn_check_group((const char_u *)name.data, (int)name.size);
+  return syn_check_group(name.data, (int)name.size);
 }
 
 Dictionary nvim__get_hl_defs(Integer ns_id, Error *err)
@@ -227,7 +227,7 @@ Dictionary nvim__get_hl_defs(Integer ns_id, Error *err)
 void nvim_set_hl(Integer ns_id, String name, Dictionary val, Error *err)
   FUNC_API_SINCE(7)
 {
-  int hl_id = syn_check_group( (char_u *)(name.data), (int)name.size);
+  int hl_id = syn_check_group(name.data, (int)name.size);
   int link_id = -1;
 
   HlAttrs attrs = dict2hlattrs(val, true, &link_id, err);