From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolai Stange <nicstange@gmail.com>
Subject: Re: [PATCH 3/3] Add NOWARN and NOERR compile conditions
Date: Mon, 03 Aug 2015 13:23:34 +0200
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In-Reply-To: <55BEA62A.6070604@redhat.com> (Tony Camuso's message of "Sun, 2
	Aug 2015 19:22:18 -0400")
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To: Tony Camuso <tcamuso@redhat.com>
Cc: Christopher Li <sparse@chrisli.org>, Josh Triplett <josh@joshtriplett.org>, Linux-Sparse <linux-sparse@vger.kernel.org>

Hi Tony,

Tony Camuso <tcamuso@redhat.com> writes:
> Here's one that might be a sparse bug.
>
> /work/linux/fs/bio.i:5368:26: error: Expected ) at end of cast operator
> /work/linux/fs/bio.i:5368:26: error: got __int128
>
> Here is the kernel source in include/linux/math64.h that causes the error.
>
> static inline __attribute__((no_instrument_function)) u64 mul_u64_u32_shr(u64 a, u32 mul, unsigned int shift)
> {
>  return (u64)(((unsigned __int128)a * mul) >> shift);
> }

This one is probably triggered by running sparse on gcc -E output.

The mul_u64_u32_shr() implementation cited by you is protected by a
  #if ... && defined(__SIZEOF_INT128__)
in include/linux/math64.h

__SIZEOF_INT128__ is #define'd by gcc but not by sparse.


The reason for your parsing error messages is probably that
declaration_specifiers() does not eat up the __int128, leaving this one
to cast_expression().

Could you please confirm that you did indeed run sparse on gcc -E
output?

Thank you,

Nicolai