patch 8.2.3659: integer overflow with large line number

Problem:    Integer overflow with large line number.
Solution:   Check for overflow. (closes #9202)
diff --git a/src/testdir/test_excmd.vim b/src/testdir/test_excmd.vim
index 773a1a3..67b95bb 100644
--- a/src/testdir/test_excmd.vim
+++ b/src/testdir/test_excmd.vim
@@ -655,4 +655,16 @@
   call assert_equal('1+1', getreg('=', 1))
 endfunc
 
+func Test_address_line_overflow()
+  if v:sizeoflong < 8
+    throw 'Skipped: only works with 64 bit long ints'
+  endif
+  new
+  call setline(1, 'text')
+  call assert_fails('|.44444444444444444444444', 'E1247:')
+  call assert_fails('|.9223372036854775806', 'E1247:')
+  bwipe!
+endfunc
+
+
 " vim: shiftwidth=2 sts=2 expandtab