diff --git a/runtime/lua/vim/diagnostic.lua b/runtime/lua/vim/diagnostic.lua
index 71bf96baee..a903f25b58 100644
--- a/runtime/lua/vim/diagnostic.lua
+++ b/runtime/lua/vim/diagnostic.lua
@@ -386,7 +386,7 @@ local function get_diagnostics(bufnr, opts, clamp)
     if not opts.lnum or d.lnum == opts.lnum then
       if clamp and vim.api.nvim_buf_is_loaded(b) then
         local line_count = buf_line_count[b] - 1
-        if (d.lnum > line_count or d.end_lnum > line_count) then
+        if (d.lnum > line_count or d.end_lnum > line_count or d.lnum < 0 or d.end_lnum < 0) then
           d = vim.deepcopy(d)
           d.lnum = math.max(math.min(d.lnum, line_count), 0)
           d.end_lnum = math.max(math.min(d.end_lnum, line_count), 0)