Compile error netio.c:349 "ignoring return value of ‘asprintf’"

[huguei]

There's a compile error from a warning in netio.c:

netio.c:349:4: error: ignoring return value of ‘asprintf’, declared with attribute warn_unused_result [-Werror=unused-result]
  349 |    asprintf(&temp, "%s%*.*s\n",
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
  350 |      or_else(writer->ps_buf, ""),
      |      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  351 |      (int)pre_len, (int)pre_len, fetch->buf);
      |      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make: *** [Makefile:60: netio.o] Error 1

It can be solved explicitly ignoring the return value with a void cast:

index ea559a5..3054c91 100644
--- a/netio.c
+++ b/netio.c
@@ -346,7 +346,7 @@ writer_func(char *ptr, size_t size, size_t nmemb, void *blob) {
                        /* concatenate this fragment (with \n) to info_buf. */
                        char *temp = NULL;
 
-                       asprintf(&temp, "%s%*.*s\n",
+                       (void) !asprintf(&temp, "%s%*.*s\n",
                                 or_else(writer->ps_buf, ""),
                                 (int)pre_len, (int)pre_len, fetch->buf);
                        DESTROY(writer->ps_buf);

[djw1149]

Thank you Hugo. I pushed a fix that instead checks the return value and does a my_panic if it's negative, as we do elsewhere.