patch 8.2.0296: mixing up "long long" and __int64 may cause problems Commit: https://github.com/vim/vim/commit/f9706e9df0e37d214fb08eda30ba29627e97a607 Author: Bram Moolenaar <Bram@vim.org> Date: Sat Feb 22 14:27:04 2020 +0100 patch 8.2.0296: mixing up "long long" and __int64 may cause problems Problem: Mixing up "long long" and __int64 may cause problems. (John Marriott) Solution: Pass varnumber_T to vim_snprintf(). Add v:numbersize.

--- a/src/json.c
+++ b/src/json.c
@@ -215,7 +215,7 @@ json_encode_item(garray_T *gap, typval_T
 
 	case VAR_NUMBER:
 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%lld",
-					      (long_long_T)val->vval.v_number);
+					      (varnumber_T)val->vval.v_number);
 	    ga_concat(gap, numbuf);
 	    break;