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References: <20231024141124.210708-1-exactlywb@ispras.ru>
From: Arsen =?utf-8?Q?Arsenovi=C4=87?= <arsen@aarsen.me>
To: exactlywb@ispras.ru
Cc: amonakov@ispras.ru, gcc-patches@gcc.gnu.org
Subject: Re: [RFC PATCH] Detecting lifetime-dse issues via Valgrind
Date: Sat, 11 Nov 2023 23:26:33 +0100
In-reply-to: <20231024141124.210708-1-exactlywb@ispras.ru>
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Hi,

I like the idea of emitting Valgrind annotations.  Instrumenting the
compiler /a little/ could make a very useful tool even more useful.

I have a minor remark, though (as someone not qualified to talk about
the middle-end bits of code), in the case that the annotation built-in
remains a libgcc bit:

exactlywb@ispras.ru writes:

> +#else
> +# define VALGRIND_MAKE_MEM_UNDEFINED(ptr, sz) __builtin_trap ()
> +#endif
> +
> +void __valgrind_make_mem_undefined (void *ptr, unsigned long sz)
> +{
> +  VALGRIND_MAKE_MEM_UNDEFINED (ptr, sz);
> +}

Would it be preferable to have a link-time error here if missing?

Have a lovely night.
=2D-=20
Arsen Arsenovi=C4=87

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