Hi Jonathan,
On Wed, Jul 22 2020, Jonathan Wakely via Gcc-patches wrote:
> libstdc++-v3/ChangeLog:
>
> * include/bits/stl_iterator.h (reverse_iterator): Constrain
> converting constructor and converting assignment operator.
> Access source iterator's data member directly instead of
> calling base().
> (move_iterator): Likewise.
> * testsuite/24_iterators/move_iterator/dr3435.cc: New test.
> * testsuite/24_iterators/reverse_iterator/dr3435.cc: New test.
>
> Tested powerpc64le-linux, committed to trunk.
>
with this patch, I fail to build 541.leela_r from SPEC INT 2017 even
when I specifically pass -std=c++98 to all compiler invocations. Is
that expected?
A simple reproducer is:
------------------------------ aaa.cpp ------------------------------
#include <vector>
typedef unsigned long long int uint64;
std::vector<uint64> ko_hash_history;
uint64 ko_hash;
bool bar(std::vector<uint64>::const_reverse_iterator fisrst,
std::vector<uint64>::const_reverse_iterator last,
std::vector<uint64>::const_reverse_iterator res);
bool foo(void) {
std::vector<uint64>::const_reverse_iterator first =
ko_hash_history.rbegin();
std::vector<uint64>::const_reverse_iterator last = ko_hash_history.rend();
std::vector<uint64>::const_reverse_iterator res;
return bar(first, last, res);
}
----------------------------------------------------------------------
$ /home/mjambor/gcc/mine/inst/bin/g++ -std=c++98 -m64 -c -O2 -g aaa.cpp
In file included from
/home/mjambor/gcc/mine/inst/include/c++/11.0.0/bits/stl_algobase.h:67,
from /home/mjambor/gcc/mine/inst/include/c++/11.0.0/vector:60,
from aaa.cpp:1:
/home/mjambor/gcc/mine/inst/include/c++/11.0.0/bits/stl_iterator.h: In
instantiation of ‘std::reverse_iterator<_Iterator>::reverse_iterator(const
std::reverse_iterator<_Iter>&) [with _Iter = __gnu_cxx::__normal_iterator<long
long unsigned int*, std::vector<long long unsigned int> >; _Iterator =
__gnu_cxx::__normal_iterator<const long long unsigned int*, std::vector<long
long unsigned int> >]’:
aaa.cpp:12:80: required from here
/home/mjambor/gcc/mine/inst/include/c++/11.0.0/bits/stl_iterator.h:203:23:
error: ‘__gnu_cxx::__normal_iterator<long long unsigned int*, std::vector<long
long unsigned int> > std::reverse_iterator<__gnu_cxx::__normal_iterator<long
long unsigned int*, std::vector<long long unsigned int> > >::current’ is
protected within this context
203 | : current(__x.current) { }
| ~~~~^~~~~~~
/home/mjambor/gcc/mine/inst/include/c++/11.0.0/bits/stl_iterator.h:146:17:
note: declared protected here
146 | _Iterator current;
| ^~~~~~~
...which is exactly the error I get from leela. The error goes away
when I use -std=c++11 instead (I promise I'll switch to building my
benchmarks with that or c++14 over the remaining of this year :-).
Is there a problem in the test (and the benchmark)? Should I file a PR?
Thanks,
Martin
