auth_token.c: add NULL initialization

This fixes

  error C4703: potentially uninitialized local pointer variable
'b64output' used

found by arm64 msvc compiler with SDL enabled.

Not sure why this is not triggered on x86/x64.

Signed-off-by: Lev Stipakov <lev@openvpn.net>
Acked-by: Antonio Quartulli <antonio@openvpn.net>
Acked-by: Arne Schwabe <arne@rfc2549.org>
Message-Id: <20220107123550.188-1-lstipakov@gmail.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg23511.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>
(cherry picked from commit 4b6073b8253dafeb425361fb55bab0f2cdc5474f)

diff --git a/src/openvpn/auth_token.c b/src/openvpn/auth_token.c
index 0ea6d18328842458b1c3e66269efaf9bec817ee9..ca7e5a4dd2faf8c955cc03c7757ffcf51b476eb2 100644 (file)
--- a/src/openvpn/auth_token.c
+++ b/src/openvpn/auth_token.c
@@ -260,7 +260,7 @@ generate_auth_token(const struct user_pass *up, struct tls_multi *multi)
     ASSERT(buf_write(&token, &timestamp, sizeof(timestamp)));
     ASSERT(buf_write(&token, hmac_output, sizeof(hmac_output)));
 
-    char *b64output;
+    char *b64output = NULL;
     openvpn_base64_encode(BPTR(&token), BLEN(&token), &b64output);
 
     struct buffer session_token = alloc_buf_gc(