[PATCH hurd] libshouldbeinlibc: fix unused result from asprintf

[dnietoc]

From: Diego Nieto Cid <dnie...@gmail.com>

    ../../libshouldbeinlibc/idvec-verify.c: In function 'verify_id':
    ../../libshouldbeinlibc/idvec-verify.c:340:9: warning: ignoring return 
value of 'asprintf' declared with attribute 'warn_unused_result' 
[-Wunused-result]
      340 |         asprintf (&prompt, "Password for %s%s:",
          |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      341 |                   is_group ? "group " : "", name);
          |                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../../libshouldbeinlibc/idvec-verify.c:343:9: warning: ignoring return 
value of 'asprintf' declared with attribute 'warn_unused_result' 
[-Wunused-result]
      343 |         asprintf (&prompt, "Password for %s %d:",
          |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      344 |                   is_group ? "group" : "user", id);
          |                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
---
 libshouldbeinlibc/idvec-verify.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/libshouldbeinlibc/idvec-verify.c b/libshouldbeinlibc/idvec-verify.c
index 64d3c573..92a47224 100644
--- a/libshouldbeinlibc/idvec-verify.c
+++ b/libshouldbeinlibc/idvec-verify.c
@@ -337,11 +337,13 @@ verify_id (uid_t id, int is_group, int multiple,
   if (multiple)
     {
       if (name)
-       asprintf (&prompt, "Password for %s%s:",
+       err = asprintf (&prompt, "Password for %s%s:",
                  is_group ? "group " : "", name);
       else
-       asprintf (&prompt, "Password for %s %d:",
+       err = asprintf (&prompt, "Password for %s %d:",
                  is_group ? "group" : "user", id);
+
+      assert_backtrace (err != -1);
     }
 
   /* Prompt the user for the password.  */
-- 
2.51.0