[Bug c++/60517] warning/error for taking address of member of a temporary object

["manu at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60517

--- Comment #7 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
(In reply to Marc Glisse from comment #6)
> (In reply to Marc Glisse from comment #5)
> > I would need a different (middle-end) warning that
> > detects return &local_var,
> 
> To confirm this, I looked at the last dangling reference I debugged,
> recompiled it with -O3 -fkeep-inline-functions, and a grep for "return &" in
> the .optimized dump showed:
>   return &one;
>   return &one;
>   return &D.495451.c_;
> (where "one" is a global variable, but D.495451 is a local variable)
> so even this trivial version of the warning would be useful.

To avoid duplicates, the front-end could just return something else, like NULL,
when it detects this case (I guess the behavior is undefined and we can do
whatever we want, no?).
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From: "sje at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/60528] New: MIPS GCC puts out complex constant incorrectly when in big-endian mode
Date: Fri, 14 Mar 2014 16:59:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id`528

            Bug ID: 60528
           Summary: MIPS GCC puts out complex constant incorrectly when in
                    big-endian mode
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sje at gcc dot gnu.org
                CC: rsandifo at gcc dot gnu.org
            Target: mips-*-*

The included test program prints out:

x = 0.634964 1.298458
x = inf inf

on MIPS instead of:

x = 0.634964 1.298458
x = 0.182506 1.163916

To reproduce the problem you need to compile the program with no optimization
(-O0) and in big-endian mode.  Little endian mode seems fine.  When I compare
the assembly language output to an earlier 4.8.1 GCC, the latest GCC output
contains the following code to store the complex constant passed in to csinh:

$LC0:
    .word    1071927711
    .word    3624173458
    .word    1073006203
    .word    1962331215

Earlier GCC compilers that worked contained:

$LC0:
    .word    1071927711
    .word    -670793838
    .word    1073006203
    .word    1962331215


Test case:

#include <stdio.h>
#include <complex.h>
#include <math.h>

int main()
{
    double complex x;
    x = 0.63496391478473613 + 1.2984575814159773I;
    printf("x = %f %f\n", creal(x), cimag(x));
    x = csinh(x);
    printf("x = %f %f\n", creal(x), cimag(x));
    return 0;
}