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Re: [PATCH 2/2] PR libstdc++/86756 Move rest of std::filesystem to libstdc++.so
On Wed, 23 Jan 2019 at 16:28, Jonathan Wakely <jwakely@redhat.com> wrote:
>
> On 09/01/19 13:53 +0100, Christophe Lyon wrote:
> >On Wed, 9 Jan 2019 at 11:11, Jonathan Wakely <jwakely@redhat.com> wrote:
> >>
> >> On 09/01/19 10:09 +0000, Jonathan Wakely wrote:
> >> >On 08/01/19 11:13 +0100, Christophe Lyon wrote:
> >> >>On Mon, 7 Jan 2019 at 15:14, Christophe Lyon <christophe.lyon@linaro.org> wrote:
> >> >>>
> >> >>>On Mon, 7 Jan 2019 at 13:39, Jonathan Wakely <jwakely@redhat.com> wrote:
> >> >>>>
> >> >>>> On 07/01/19 09:48 +0000, Jonathan Wakely wrote:
> >> >>>> >On 07/01/19 10:24 +0100, Christophe Lyon wrote:
> >> >>>> >>Hi Jonathan
> >> >>>> >>
> >> >>>> >>On Sun, 6 Jan 2019 at 23:37, Jonathan Wakely <jwakely@redhat.com> wrote:
> >> >>>> >>>
> >> >>>> >>>Move std::filesystem directory iterators and operations from
> >> >>>> >>>libstdc++fs.a to main libstdc++ library. These components have many
> >> >>>> >>>dependencies on OS support, which is not available on all targets. Some
> >> >>>> >>>additional autoconf checks and conditional compilation is needed to
> >> >>>> >>>ensure the files will build for all targets. Previously this code was
> >> >>>> >>>not compiled without --enable-libstdcxx-filesystem-ts but the C++17
> >> >>>> >>>components should be available for all hosted builds.
> >> >>>> >>>
> >> >>>> >>>The tests for these components no longer need to link to libstdc++fs.a,
> >> >>>> >>>but are not expected to pass on all targets. To avoid numerous failures
> >> >>>> >>>on targets which are not expected to pass the tests (due to missing OS
> >> >>>> >>>functionality) leave the dg-require-filesystem-ts directives in place
> >> >>>> >>>for now. This will ensure the tests only run for builds where the
> >> >>>> >>>filesystem-ts library is built, which presumably means some level of OS
> >> >>>> >>>support is present.
> >> >>>> >>>
> >> >>>> >>>
> >> >>>> >>>Tested x86_64-linux (old/new string ABIs, 32/64 bit), x86_64-w64-mingw32.
> >> >>>> >>>
> >> >>>> >>>Committed to trunk.
> >> >>>> >>>
> >> >>>> >>
> >> >>>> >>After this commit (r267616), I've noticed build failures for my
> >> >>>> >>newlib-based toolchains:
> >> >>>> >>aarch64-elf, arm-eabi:
> >> >>>> >>
> >> >>>> >>In file included from
> >> >>>> >>/tmp/5241593_7.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/libstdc++-v3/src/c++17/fs_ops.cc:57:
> >> >>>> >>/tmp/5241593_7.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/libstdc++-v3/src/c++17/../filesystem/ops-common.h:142:11:
> >> >>>> >>error: '::truncate' has not been declared
> >> >>>> >> 142 | using ::truncate;
> >> >>>> >> | ^~~~~~~~
> >> >>>> >>/tmp/5241593_7.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/libstdc++-v3/src/c++17/fs_ops.cc:
> >> >>>> >>In function 'void std::filesystem::resize_file(const
> >> >>>> >>std::filesystem::__cxx11::path&, uintmax_t, std::error_code&)':
> >> >>>> >>/tmp/5241593_7.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/libstdc++-v3/src/c++17/fs_ops.cc:1274:19:
> >> >>>> >>error: 'truncate' is not a member of 'posix'
> >> >>>> >>1274 | else if (posix::truncate(p.c_str(), size))
> >> >>>> >> | ^~~~~~~~
> >> >>>> >>make[5]: *** [fs_ops.lo] Error 1
> >> >>>> >>
> >> >>>> >>I'm not sure if there's an obvious fix? Note that I'm using a rather
> >> >>>> >>old newlib version, if that matters.
> >> >>>> >
> >> >>>> >That's probably the reason, as I didn't see this in my tests with
> >> >>>> >newlib builds.
> >> >>>> >
> >> >>>> >The fix is to add yet another autoconf check and guard the uses of
> >> >>>> >truncate with a _GLIBCXX_USE_TRUNCATE macro. I'll do that now ...
> >> >>>>
> >> >>>>
> >> >>>> Should be fixed with this patch, committed to trunk as r267647.
> >> >>>>
> >> >>>
> >> >>>Yes, it works. Thanks!
> >> >>>
> >> >>
> >> >>Hi Jonathan,
> >> >>
> >> >>So... this was a confirmation that the GCC build succeeded, not that
> >> >>the tests pass :)
> >> >>
> >> >>And there are actually a couple new errors with my newlib-based toolchains:
> >> >>FAIL: 27_io/filesystem/operations/all.cc (test for excess errors)
> >> >>FAIL: 27_io/filesystem/operations/resize_file.cc (test for excess errors)
> >> >>FAIL: 27_io/filesystem/path/generation/normal2.cc (test for excess errors)
> >> >>which are also UNRESOLVED, because of link-time undefined reference to `chdir',
> >> >>chmod, mkdir, pathconf and getcwd.
> >> >
> >> >Ah, I was assuming if <unistd.h> is present, then those basic
> >> >functions will be present. More autoconf checks needed, I guess.
> >> >That isn't hard to do, just tedious.
> >> >
> >> >>On aarch64, I'm seeing an addtional:
> >> >>FAIL: 27_io/filesystem/path/compare/strings.cc execution test
> >> >>because:
> >> >>/libstdc++-v3/testsuite/27_io/filesystem/path/compare/strings.cc:39:
> >> >>void test01(): Assertion 'p.compare(p0) == p.compare(s0)' failed.
> >> >
> >> >Odd, I don't know why that would be target-specific. It's probably
> >> >just latent on other targets. I'll try to reproduce it on my aarch64
> >> >system, but it will take a while to build current trunk.
> >> >
> >> >If you have time, could you please apply this patch, re-run that test
> >>
> >> *This* patch:
> >>
> >> --- a/libstdc++-v3/testsuite/27_io/filesystem/path/compare/strings.cc
> >> +++ b/libstdc++-v3/testsuite/27_io/filesystem/path/compare/strings.cc
> >> @@ -36,6 +36,7 @@ test01()
> >> path p(s);
> >> VERIFY( p.compare(s) == 0 );
> >> VERIFY( p.compare(s.c_str()) == 0 );
> >> + __builtin_printf("Comparing %s as path:%d as string:%d\n", s.c_str(), p.compare(p0), p.compare(s0));
> >> VERIFY( p.compare(p0) == p.compare(s0) );
> >> VERIFY( p.compare(p0) == p.compare(s0.c_str()) );
> >> }
> >>
> >>
> >>
> >>
> >> >(cd $target/libstdc++-v3 && make check
> >> >RUNTESTFLAGS=conformance.exp=*/path/compare/strings/cc) and send me
> >> >the output from the $target/libstdc++-v3/testsuite/libstdc++.log file?
> >> >
> >> >On x86_64 I get:
> >> >
> >> >Comparing as path:-1 as string:-1
> >> >Comparing / as path:-1 as string:-1
> >> >Comparing // as path:-1 as string:-1
> >> >Comparing /. as path:-51 as string:-51
> >> >Comparing /./ as path:-51 as string:-51
> >> >Comparing /a as path:-2 as string:-2
> >> >Comparing /a/ as path:-1 as string:-1
> >> >Comparing /a// as path:-1 as string:-1
> >> >Comparing /a/b/c/d as path:1 as string:1
> >> >Comparing /a//b as path:1 as string:1
> >> >Comparing a as path:-1 as string:-1
> >> >Comparing a/b as path:-1 as string:-1
> >> >Comparing a/b/ as path:-1 as string:-1
> >> >Comparing a/b/c as path:-1 as string:-1
> >> >Comparing a/b/c.d as path:-1 as string:-1
> >> >Comparing a/b/.. as path:-1 as string:-1
> >> >Comparing a/b/c. as path:-1 as string:-1
> >> >Comparing a/b/.c as path:-1 as string:-1
> >> >PASS: 27_io/filesystem/path/compare/strings.cc execution test
> >> >
> >
> >Here is what I have on aarch64-none-elf:
> >Comparing as path:-1 as string:-1^M
> >Comparing / as path:-1 as string:-1^M
> >Comparing // as path:-1 as string:-1^M
> >Comparing /. as path:-102 as string:-51^M
> >/libstdc++-v3/testsuite/27_io/filesystem/path/compare/strings.cc:40:
> >void test01(): Assertion 'p.compare(p0) == p.compare(s0)' failed.^M
> >^M
> >*** EXIT code 4242^M
> >emu: host signal 6^M
> >FAIL: 27_io/filesystem/path/compare/strings.cc execution test
>
> This is a strange one. With my aarch64-unknown-linux-gnu trunk build I get:
>
> Comparing /. as path:-51 as string:-51
>
> Which suggests it's a newlib vs glibc difference, but this target uses
> glibc (right?) and has the same FAIL:
> https://gcc.gnu.org/ml/gcc-testresults/2019-01/msg02276.html
Yes, it uses glibc-2.28
That build has this in its libstdc++.log:
/home/tcwg-buildslave/workspace/tcwg-buildfarm_0/snapshots/gcc.git~master_rev_2e9ceebcd7618d0e068e0029b43cd75d679022d7/libstdc++-v3/testsuite/27_io/filesystem/path/compare/strings.cc:39:
void test01(): Assertion 'p.compare(p0) == p.compare(s0)' failed.
timeout: the monitored command dumped core
FAIL: 27_io/filesystem/path/compare/strings.cc execution test
>
> The test should be reducable to simply:
>
> // { dg-options "-std=gnu++17" }
> #include <string>
> #include <string_view>
>
> int main()
> {
> std::string_view s0 = "a";
> std::string p0(s0);
> std::string p(".");
> __builtin_printf("as path:%d as string:%d\n", p.compare(p0), p.compare(s0));
> }
>
> Again, I get -51 and -51 for this. Could you test it on
> aarch64-none-elf?
>
> In terms of what the standard requires, this comparison is based on
> strcmp, i.e. it only specifies a result less than zero, equal to zero,
> or greater than zero. But I'd like to know why the comparisons aren't
> returning the same consistent value.
>
I get:
as path:-102 as string:-102