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From: "drepper at redhat dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/25521]  New: change semantics of const volatile variables
Date: Wed, 21 Dec 2005 18:57:00 -0000	[thread overview]
Message-ID: <bug-25521-700@http.gcc.gnu.org/bugzilla/> (raw)

In math code we often have to make sure the compiler does not fold operations
at compile time.  In glibc we use variable declared as

  static const volatile double foo = 42.0;

The problem is that gcc moves such variables into .data.  But we could achieve
that easily by leaving out the 'const'.  What is needed is a method to achieve
volatile behavior while having the variable in .rodata (and .rodata.cst8 etc).

I therefore would like to ask for a change in the compiler which preserves the
'const' in the presence of 'volatile' and place the variable in read-only
memory.


-- 
           Summary: change semantics of const volatile variables
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: drepper at redhat dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25521


             reply	other threads:[~2005-12-21 18:57 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-12-21 18:57 drepper at redhat dot com [this message]
2005-12-21 19:17 ` [Bug middle-end/25521] " gdr at integrable-solutions dot net
2005-12-21 19:38 ` drepper at redhat dot com
2005-12-21 19:54 ` gdr at integrable-solutions dot net

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