diff --git a/src/util/vircommand.c b/src/util/vircommand.c
index 774038e536..2df71014f8 100644
--- a/src/util/vircommand.c
+++ b/src/util/vircommand.c
@@ -1775,7 +1775,7 @@ virCommandSetSendBuffer(virCommandPtr cmd,
                         int fd,
                         unsigned char *buffer, size_t buflen)
 {
-    size_t i = virCommandGetNumSendBuffers(cmd);
+    size_t i;
 
     if (!cmd || cmd->has_error)
         return -1;
@@ -1787,6 +1787,7 @@ virCommandSetSendBuffer(virCommandPtr cmd,
         return -1;
     }
 
+    i = virCommandGetNumSendBuffers(cmd);
     if (VIR_REALLOC_N(cmd->sendBuffers, i + 1) < 0) {
         cmd->has_error = ENOMEM;
         return -1;
diff --git a/src/util/vircommand.h b/src/util/vircommand.h
index c2abc7b2c3..74574e3fb1 100644
--- a/src/util/vircommand.h
+++ b/src/util/vircommand.h
@@ -149,7 +149,7 @@ void virCommandSetWorkingDirectory(virCommandPtr cmd,
 int virCommandSetSendBuffer(virCommandPtr cmd,
                             int fd,
                             unsigned char *buffer, size_t buflen)
-    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(3);
+    ATTRIBUTE_NONNULL(3);
 
 void virCommandSetInputBuffer(virCommandPtr cmd,
                               const char *inbuf) ATTRIBUTE_NONNULL(2);