c++/1738: template function with volatile formal parameter confuses compiler

c++/1738: template function with volatile formal parameter confuses compiler

[mps]

>Number:         1738
>Category:       c++
>Synopsis:       template function with volatile formal parameter confuses compiler
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          rejects-legal
>Submitter-Id:   net
>Arrival-Date:   Mon Jan 22 18:56:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Michael Shepanski
>Release:        2.95.2 19991024
>Organization:
>Environment:
AIX power-pc
>Description:
template <class T>
void f (volatile T x)  {}

main ()
{
    volatile int *vip = 0;
    // the following instantiation of f should
    // have T="int *", and therefore have a
    // formal parameter type of "volatile int *",
    // which matches the actual parameter.
    // So why does g++ reject it?
    f<int *> (vip);
}
>How-To-Repeat:
Compile the code given in the "Description:" box.
>Fix:
Please
>Release-Note:
>Audit-Trail:
>Unformatted:
>From pedwards@disaster.jaj.com Sun Apr 01 00:00:00 2001
From: Phil Edwards <pedwards@disaster.jaj.com>
To: nobody@gcc.gnu.org
Cc: gcc-prs@gcc.gnu.org
Subject: Re: c++/1571: g++ is confused with by code that typedef's wchar_t.
Date: Sun, 01 Apr 2001 00:00:00 -0000
Message-id: <20010107050600.2279.qmail@sourceware.cygnus.com>
X-SW-Source: 2001-q1/msg00070.html
Content-length: 1095

The following reply was made to PR c++/1571; it has been noted by GNATS.

From: Phil Edwards <pedwards@disaster.jaj.com>
To: cgd@sibyte.com
Cc: gcc-gnats@gcc.gnu.org, don@pixstream.com
Subject: Re: c++/1571: g++ is confused with by code that typedef's wchar_t.
Date: Sun, 7 Jan 2001 00:07:22 -0500

 On Sat, Jan 06, 2001 at 01:37:55AM -0000, cgd@sibyte.com wrote:
 > >Description:
 > g++ seems to to mishandle code which typedef's wchar_t,
 > emitting an error when none is appropriate.
 
 Sure it's appropriate.  In C++, wchar_t is a builtin type, like 'int' and
 'char'.  You can't typedef it.
 
 
 > (Several of NetBSD's headers typedef wchar_t as
 > appropriate.)
 
 For C, wchar_t is typedef'd, but not for C++.  There should be conditional
 complication guards around such typedefs, e.g.,
 
     #ifndef __cplusplus
     typedef wchar_t int;
     #endif
 
 -- 
 pedwards at disaster dot jaj dot com  |  pme at sources dot redhat dot com
 devphil at several other less interesting addresses in various dot domains
 The gods do not protect fools.  Fools are protected by more capable fools.
>From etienne.lorrain@masroudeau.com Sun Apr 01 00:00:00 2001
From: etienne.lorrain@masroudeau.com
To: gcc-gnats@gcc.gnu.org
Subject: c/1995: position dependency in asm("" : ...  : : )
Date: Sun, 01 Apr 2001 00:00:00 -0000
Message-id: <20010215101145.3117.qmail@sourceware.cygnus.com>
X-SW-Source: 2001-q1/msg01302.html
Content-length: 1687

>Number:         1995
>Category:       c
>Synopsis:       position dependency in asm("" : ...  : : )
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Feb 15 02:16:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Etienne LORRAIN
>Release:        unknown-1.0
>Organization:
>Environment:
gcc version 2.97 20010212 on i386/Linux (www.codesourcery.com) for "inconsistent operand constraints in an `asm'"
Seen with error "asm too many reload" on gcc-2.95-2
>Description:
Compile with or without -DASM_TOO_MANY_RELOAD, _and_ with
at least -O for inlines, this code (the only difference is that the "+r" parameter is the last output or not):

extern unsigned dummy;
unsigned dummyfct (unsigned);
extern inline unsigned xchgl (unsigned adr, unsigned value)
  {
  unsigned short scratch;

#ifdef ASM_TOO_MANY_RELOAD
  asm volatile ("
        pushl   %2
        popw    %w0
        popw    %%fs
        xchgl   %%fs:(%w0),%1
        "
        : "=bSDB" (scratch), "+r" (value) : "g" (adr) : "memory");
#else
  asm volatile ("
        pushl   %2
        popw    %w1
        popw    %%fs
        xchgl   %%fs:(%w1),%0
        "
        : "+r" (value), "=bSDB" (scratch) : "g" (adr) : "memory");
#endif
  return value;
  }

unsigned fct (unsigned irq, unsigned fct_faradr)
  {
  if (dummy)
      return dummyfct (irq);
    else
      return xchgl (4*irq, fct_faradr);
  }
>How-To-Repeat:
http://www.codesourcery.com/cgi-bin/gcc-compile.py
See compiler messages, with:
"-O -DASM_TOO_MANY_RELOAD" or "-O"
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: