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Date: Wed, 22 Jan 1997 15:43:21 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199701220443.PAA02264@godzilla.zeta.org.au>
To: jlemon@americantv.com, phk@freebsd.org
Subject: Re: GCC or TEXINFO bug...
Cc: current@freebsd.org
Sender: owner-current@freebsd.org
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>Compiling with -O3 inlines functions.  However the function that is being
>inlined in makeinfo.c (add_word_args()) is a vararg function and must not be 
>inlined. 
>
>The code in question is K&R style, and AFIK, there is no way for the compiler
>to determine that the function uses vararg.  Either change the code to use
>prototypes, or use stdarg, or add a directive to prevent inlining.

Not declaring a varargs function as varargs before it is used gives
undefined behaviour.

However, in practice the bug is probably in FreeBSD's <varargs.h>, which
doesn't use gcc's __builtin_next_arg().  gcc should notice that it is
used and not inline functions that have it.  <stdarg.h.> uses it, but I
think there's another gcc builtin that it should be using.

Bruce