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Subject: Re: [PATCH] KEYS: trusted: fix -Wvarags warning
To:     James Bottomley <jejb@linux.ibm.com>, ndesaulniers@google.com,
        dhowells@redhat.com
Cc:     natechancellor@gmail.com, ebiggers@google.com,
        Mimi Zohar <zohar@linux.vnet.ibm.com>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        linux-integrity@vger.kernel.org, keyrings@vger.kernel.org,
        linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org
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From:   Denis Kenzior <denkenz@gmail.com>
Message-ID: <16de2bb3-815a-f534-4618-af854c906017@gmail.com>
Date:   Fri, 12 Oct 2018 10:44:40 -0500
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Hi James,

>> So instead of having unsigned char h3, can't we simply have bool h3
>> or unsigned int h3?
> 
> Given the ambiguity in the standards, the safe thing that will work for
> all time and all potential compilers is a char *
> 

All right.  You state this with certainty, but I'd still like you to 
educate me why?

 From the links provided in the patch it seems that one cannot pass 
char/float/short to va_start().  Fair enough.  So if we make h3 an 
unsigned int, the issue goes away, no?

  int TSS_authhmac(unsigned char *digest, const unsigned char *key,
                         unsigned int keylen, unsigned char *h1,
-                       unsigned char *h2, unsigned char h3, ...);
+                       unsigned char *h2, unsigned int h3, ...);

Regards,
-Denis