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From: Kai Tietz <ktietz70@googlemail.com>
To: Paolo Carlini <paolo.carlini@oracle.com>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>,
	"libstdc++" <libstdc++@gcc.gnu.org>
Subject: Re: [patch libstdc++]: Fix LLP64 pointer-size issues for cxxabi, eh_alloc, and hash_bytes
Date: Fri, 21 Dec 2012 09:48:00 -0000	[thread overview]
Message-ID: <CAEwic4YCxiCmnd5pY-Ra7vq4AJ7rkwwe75E=YstOeEWDWJHNeg@mail.gmail.com> (raw)
In-Reply-To: <50D42E31.30807@oracle.com>

2012/12/21 Paolo Carlini <paolo.carlini@oracle.com>:
> On 12/21/2012 10:36 AM, Kai Tietz wrote:
>>
>> well, issue isn't that 'long' is always 'ptrdiff_t'.
>
> But then, if we just change the type without paying attention to size (and
> alignment) aren't we looking for BIG ABI trouble?!?

Huh?  We have ABI-trouble due long is  too small to hold a
pointer-diff for llp64.  Intended is here 'pointer-size' AFAICS in
code, but with wrong assumption that a 'long' is always long enough.

 Btw I just checked all targets we have right now in gcc.  The type
ptrdiff_t is always either 'long', or 'int' (ilp32, lp64), and 'long
long' for LLP64.  Means ptrdiff_t gets always equal (or bigger) to
biggest pointer-size for target (AFAICS).

Kai

  reply	other threads:[~2012-12-21  9:48 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-12-21  8:00 Kai Tietz
2012-12-21  9:12 ` Marc Glisse
2012-12-21  9:13 ` Paolo Carlini
2012-12-21  9:16   ` Kai Tietz
2012-12-21  9:32     ` Paolo Carlini
2012-12-21  9:36       ` Kai Tietz
2012-12-21  9:39         ` Paolo Carlini
2012-12-21  9:48           ` Kai Tietz [this message]
2012-12-21  9:59             ` Kai Tietz
2012-12-21 10:02               ` Paolo Carlini
2012-12-21 15:04             ` Gabriel Dos Reis
2012-12-21 15:54               ` Kai Tietz
2012-12-21 14:59 ` Gabriel Dos Reis
2012-12-21 10:13 Uros Bizjak
2012-12-21 10:16 ` Kai Tietz

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