[Bug libstdc++/77268] New: Vector erase call destructor for last element twice and doesn't call destructor for eased element.

["jdinardo at nycap dot rr.com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77268

            Bug ID: 77268
           Summary: Vector erase call destructor for last element twice
                    and doesn't call destructor for eased element.
           Product: gcc
           Version: 6.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jdinardo at nycap dot rr.com
  Target Milestone: ---

Created attachment 39465
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39465&action=edit
Small  33 line program which shows the problem.

Vector erase is asked to erase 3rd element of 5 element vector. The
destructor for the last(fifth) element is called twice and the destructor
for the 3rd element is not called. The 3rd element is erased but the malloced
memory is never freed. BUG 47305 seems to imply that this is ok. If that is the
case, then pleas ignore this.

VERSION - g++ -v
    Using built-in specs.
    COLLECT_GCC=g++
    COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/6.1.1/lto-wrapper
    Target: x86_64-pc-linux-gnu
    Configured with: /build/gcc/src/gcc/configure --prefix=/usr
--libdir=/usr/li
    Thread model: posix
    gcc version 6.1.1 20160802 (GCC)

System is Arch Linux

MAKEFILE
    CPPFLAGS=-g -Wall -lfltk
    ALL:hello t1 v1

MAKEFILE OUTPUT - no warnings or errors
    g++  -g -Wall -lfltk   v1.cc   -o v1

COMMAND LINE
    v1

SMALL 33 LINE TEST PROGRAM 
    Included as attachment