[Bug libstdc++/111162] New: signed integer overflow triggered by std::chrono::parse

[Bug libstdc++/111162] New: signed integer overflow triggered by std::chrono::parse

[gcc at pauldreik dot se]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111162

            Bug ID: 111162
           Summary: signed integer overflow triggered by
                    std::chrono::parse
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gcc at pauldreik dot se
  Target Milestone: ---

The following program:

#include <chrono>
#include <format>
#include <sstream>
int main() {
    std::istringstream is("21474837");
    std::chrono::minutes x;
    is >> std::chrono::parse("%8C", x);
}

invokes undefined behaviour. If compiled with the current gcc trunk, one gets
this when executed:
/opt/compiler-explorer/gcc-trunk-20230824/include/c++/14.0.0/bits/chrono_io.h:3174:20:
runtime error: signed integer overflow: 21474837 * 100 cannot be represented in
type 'int'

link to reproducer (uses gcc trunk, may go stale quick):
https://godbolt.org/z/h617GT4EY

[Bug libstdc++/111162] signed integer overflow triggered by std::chrono::parse

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111162

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Target Milestone|---                         |13.3
             Status|UNCONFIRMED                 |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |redi at gcc dot gnu.org
   Last reconfirmed|                            |2023-08-26

[Bug libstdc++/111162] signed integer overflow triggered by std::chrono::parse

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111162

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Testing a patch ...

[Bug libstdc++/111162] signed integer overflow triggered by std::chrono::parse

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111162

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jonathan Wakely <redi@gcc.gnu.org>:

https://gcc.gnu.org/g:207c507499d23f0176cbfdfe96d3cd50dec39584

commit r14-3609-g207c507499d23f0176cbfdfe96d3cd50dec39584
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Tue Aug 29 13:07:21 2023 +0100

    libstdc++: Do not allow chrono::parse to overflow for %C [PR111162]

    libstdc++-v3/ChangeLog:

            PR libstdc++/111162
            * include/bits/chrono_io.h (_Parser::Operator()): Check %C
            values are in range of year::min() to year::max().
            * testsuite/std/time/parse.cc: Check out of range centuries.

[Bug libstdc++/111162] signed integer overflow triggered by std::chrono::parse

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111162

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
   Target Milestone|13.3                        |14.0
         Resolution|---                         |FIXED

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This should be fixed now, thanks for the report.