[Bug libstdc++/66485] New: std::string single-character assignment operator

[Bug libstdc++/66485] New: std::string single-character assignment operator

[yurivkhan at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66485

            Bug ID: 66485
           Summary: std::string single-character assignment operator
           Product: gcc
           Version: 4.8.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: yurivkhan at gmail dot com
  Target Milestone: ---

gcc’s implementation of std::basic_string contains a non-standard and very
surprising operator= which accepts a single character or anything that is
implicitly castable thereto.

To reproduce:

===
#include <iostream>
#include <string>

int main()
{
    std::string s;
    s = 42;
    std::cout << s << "\n";
}
===

$ g++ --version
g++ (Ubuntu 4.8.2-19ubuntu1) 4.8.2[…]

$ g++ test.cpp
(with any of -std= variations, with or without -Wall -pedantic)

Observed behavior: compiles, runs, outputs a single character * (asterisk).

Expected behavior: compilation error, because the standard does not define any
such operator=.
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Subject: [Bug target/66473] ICE: in extract_insn, at recog.c:2343 (unrecognizable insn) with -mavx512f
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66473

--- Comment #5 from Kirill Yukhin <kyukhin at gcc dot gnu.org> ---
(In reply to Uroš Bizjak from comment #3)
> Kirill, you have much better facilities for testing, do you want to take the
> proposed patch from here?

Your patch is fine for sure. No AVX-512* tests fail.
The only nit is that I that I think we need regtest in patch as well.
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Subject: [Bug target/66473] ICE: in extract_insn, at recog.c:2343 (unrecognizable insn) with -mavx512f
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66473

--- Comment #6 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to Kirill Yukhin from comment #5)

> Your patch is fine for sure. No AVX-512* tests fail.
> The only nit is that I that I think we need regtest in patch as well.

Yep, it will be added when the patch is submitted later today.
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Subject: [Bug tree-optimization/60656] [4.8 regression] x86 vectorization produces wrong code
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id`656

--- Comment #18 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Wed Jun 10 12:53:09 2015
New Revision: 224327

URL: https://gcc.gnu.org/viewcvs?rev"4327&root=gcc&view=rev
Log:
2015-06-10  Richard Biener  <rguenther@suse.de>

        Backport from mainline
        2014-04-04  Cong Hou  <congh@google.com>

        PR tree-optimization/60656
        * tree-vect-stmts.c (supportable_widening_operation):
        Fix a bug that elements in a vector with vect_used_by_reduction
        property are incorrectly reordered when the operation on it is not
        consistant with the one in reduction operation.

        * gcc.dg/vect/pr60656.c: New test.

        2014-01-31  Richard Biener  <rguenther@suse.de>

        PR middle-end/59990
        * builtins.c (fold_builtin_memory_op): Make sure to not
        use a floating-point mode or a boolean or enumeral type for
        the copy operation.

        * gcc.dg/torture/pr59990.c: New testcase.
        * gcc.target/i386/pr49168-1.c: Adjust.

Added:
    branches/gcc-4_8-branch/gcc/testsuite/gcc.dg/torture/pr59990.c
    branches/gcc-4_8-branch/gcc/testsuite/gcc.dg/vect/pr60656.c
Modified:
    branches/gcc-4_8-branch/gcc/ChangeLog
    branches/gcc-4_8-branch/gcc/builtins.c
    branches/gcc-4_8-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_8-branch/gcc/testsuite/gcc.target/i386/pr49168-1.c
    branches/gcc-4_8-branch/gcc/tree-vect-stmts.c

[Bug libstdc++/66485] std::string single-character assignment operator

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66485

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |INVALID

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
See (4) at http://en.cppreference.com/w/cpp/string/basic_string/operator%3D

c.f. http://cplusplus.github.io/LWG/lwg-active.html#2372

[Bug libstdc++/66485] std::string single-character assignment operator

[yurivkhan at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66485

--- Comment #2 from Yuri Khan <yurivkhan at gmail dot com> ---
Right, I somehow missed it. The overload is there. Sorry for the noise.