yml: don’t overwrite errors from yml_parser_parse()

When we detect an error in yml_parser_parse(), we handle that
specifically, and then jump to the generic error handler.

The generic error handler overwrites the previously formatted error
before cleaning up and returning.

This meant that a) the actual error message was lost, and replaced
with a generic “unknown error”, and b) the dynamically allocated error
string buffer was leaked.

CHANGELOG.md

@@ -9,6 +9,11 @@
 ### Deprecated
 ### Removed
 ### Fixed
+
+* YAML parsing error messages being replaced with a generic “unknown error”.
+* Memory leak when a YAML parsing error was encoutered.
+
+
 ### Security
 ### Contributors
 

yml.c

@@ -383,7 +383,7 @@ yml_load(FILE *yml, char **error)
                     yaml.context != NULL ? yaml.context : "");
             }
 
-            goto err;
+            goto err_no_error_formatting;
         }
 
         switch (event.type) {
@@ -550,6 +550,8 @@ err:
                  yaml.mark.line + 1, yaml.mark.column);
     }
 
+err_no_error_formatting:
+
     yml_destroy(root);
     yaml_parser_delete(&yaml);
     return NULL;