diff --git a/c/cli/mlrcli.c b/c/cli/mlrcli.c
index 7923bb7e4..3c5ea649d 100644
--- a/c/cli/mlrcli.c
+++ b/c/cli/mlrcli.c
@@ -329,8 +329,6 @@ static void main_usage_data_format_options(FILE* o, char* argv0) {
 	fprintf(o, "                                  e.g. '{\"a\":{\"b\":3}}' becomes a:b => 3 for\n");
 	fprintf(o, "                                  non-JSON formats. Defaults to %s.\n",
 		DEFAULT_JSON_FLATTEN_SEPARATOR);
-	// xxx fix this cmt once lrec_reader_stdio_json is complete
-	fprintf(o, "  NOTE: --json and --ijson are currently under construction, but --ojson works.\n");
 	fprintf(o, "\n");
 	fprintf(o, "  -p is a keystroke-saver for --nidx --fs space --repifs\n");
 	fprintf(o, "\n");
diff --git a/c/input/lrec_reader_mmap_json.c b/c/input/lrec_reader_mmap_json.c
index 6781bc939..5387fb814 100644
--- a/c/input/lrec_reader_mmap_json.c
+++ b/c/input/lrec_reader_mmap_json.c
@@ -143,13 +143,16 @@ static void lrec_reader_mmap_json_sof(void* pvstate, void* pvhandle) {
 		parsed_top_level_json = json_parse_ex(item_start, length, error_buf, &item_start, &settings);
 
 		if (parsed_top_level_json == NULL) {
-			fprintf(stderr, "Unable to parse JSON data: %s\n", error_buf);
+			fprintf(stderr, "%s: Unable to parse JSON data: %s\n", error_buf, MLR_GLOBALS.argv0);
 			exit(1);
 		}
 
 		// The lrecs have their string pointers pointing into the parsed-JSON objects (for
 		// efficiency) so it's important we not free the latter until our free method.
-		reference_json_objects_as_lrecs(pstate->precords, parsed_top_level_json, pstate->json_flatten_separator);
+		if (!reference_json_objects_as_lrecs(pstate->precords, parsed_top_level_json, pstate->json_flatten_separator)) {
+			fprintf(stderr, "%s: Unable to parse JSON data.\n", MLR_GLOBALS.argv0);
+			exit(1);
+		}
 
 		if (item_start == NULL)
 			break;
diff --git a/c/mapping/mapper_reshape.c b/c/mapping/mapper_reshape.c
index 98af5f8cd..c5b892409 100644
--- a/c/mapping/mapper_reshape.c
+++ b/c/mapping/mapper_reshape.c
@@ -294,8 +294,9 @@ static sllv_t* mapper_reshape_wide_to_long_no_regex_process(lrec_t* pinrec, cont
 	for (sllse_t* pe = pstate->input_field_names->phead; pe != NULL; pe = pe->pnext) {
 		char* key = pe->value;
 		char* value = lrec_get(pinrec, key);
-		if (value != NULL)
-			lhmss_put(pairs, key, value, NO_FREE);
+		if (value != NULL) {
+			lhmss_put(pairs, mlr_strdup_or_die(key), mlr_strdup_or_die(value), FREE_ENTRY_KEY|FREE_ENTRY_VALUE);
+		}
 	}
 
 	// Unset the lrec keys after iterating over them, rather than during
@@ -332,7 +333,8 @@ static sllv_t* mapper_reshape_wide_to_long_regex_process(lrec_t* pinrec, context
 		for (sllve_t* pf = pstate->input_field_regexes->phead; pf != NULL; pf = pf->pnext) {
 			regex_t* pregex = pf->pvvalue;
 			if (regmatch_or_die(pregex, pe->key, 0, NULL)) {
-				lhmss_put(pairs, pe->key, pe->value, NO_FREE);
+				lhmss_put(pairs, mlr_strdup_or_die(pe->key), mlr_strdup_or_die(pe->value),
+					FREE_ENTRY_KEY|FREE_ENTRY_VALUE);
 				break;
 			}
 		}
diff --git a/c/todo.txt b/c/todo.txt
index 33d88a228..cc5a611a0 100644
--- a/c/todo.txt
+++ b/c/todo.txt
@@ -61,8 +61,12 @@ TOP-OF-LIST SUMMARY
 TOP-OF-LIST DETAILS
 
 * JSON I/O:
+  ! string-preservation for doubles !
+  ! UT !
+  ! mlr --json reshape -i x,y -o item,value rec.json
+
   ! acknowledgement to mld: https://github.com/udp/json-parser
-  ! stdio version. & prefer stremable version with fgetc rather than pointer-math.
+  o wishlist: streamable version with fgetc rather than pointer-math.
   - on output, check 1st if mlhmmv is necessary? or just always?
   - cover x 2
   - define 'tabular JSON' by example @ mld
@@ -70,16 +74,9 @@ TOP-OF-LIST DETAILS
     - programmable allow-this-on-input flag
     - programmable allow-this-on-output flag
     - programmable flatten-separator
-  ? or support multi-level lrecs??
   o hp re :)
   ! JSON/join UT. both/left/right json cases.
 
-  o bug:
-
-    $ mlr --jlistwrap --jvstack --json cat ~/bak/bmx/bookmarks-2016-02-02.json 
-    mlr: found array item within JSON object. This is valid but unmillerable JSON.
-    ]
-
 ? env vars??
 
 * doc: