compile error :folly/folly/test/base64_test.cpp

[yxbu1996]

folly/folly/test/base64_test.cpp:73:3: error: non-constant condition for static assertion static_assert(toEncode == decoded);

centos7 linux 4.18 gcc7.3.1

[Orvid]

Could you try again with https://github.com/facebook/folly/commit/437b29dd062a40c741b2147827025a2f413b76c7 ? I suspect it may still have issues building the test on some older versions of libstdc++ due to certain things in the standard library not being marked as constexpr.

Does this give any further error about why it considers one of these to be non-constant?

[donsbot]

Seeing similar. https://gist.github.com/donsbot/40bf2089f1b98dcc7b49c913f2e85826#file-gistfile1-txt-L366

Base64SpecialCasesTest.cpp:52:10: error: no viable overloaded '='
    data = {dataBuf.begin(), o};

 note: initializer of 'staticTestCases' is not a constant expression
    if (!testRunner(TestCase{test})) {

Debian 11, clang 11. Similar with gcc-9,10.

Can build if I checkout c4672f5fd4c8ca9da8e2ecf4fda38e4eae82d544

[donsbot]

This is preventing the glean ci from building with either clang or gcc.

https://github.com/facebookincubator/Glean/runs/7550851666?check_suite_focus=true#step:14:832

/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git/folly/detail/base64_detail/tests/Base64PlatformTest.cpp:63:7: note: non-constexpr function 'fill' cannot be used in a constant expression
  res.fill(0);
      ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/array:117:7: note: declared here
      fill(const value_type& __u)
      ^
1 error generated.

or with gcc:

/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git/folly/detail/base64_detail/tests/Base64PlatformTest.cpp: In function ‘constexpr std::array<unsigned char, 16> folly::detail::base64_detail::{anonymous}::expectedPackIndexesToBytes(std::array<unsigned char, 16>)’:
/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git/folly/detail/base64_detail/tests/Base64PlatformTest.cpp:63:11: error: call to non-‘constexpr’ function ‘void std::array<_Tp, _Nm>::fill(const value_type&) [with _Tp = unsigned char; long unsigned int _Nm = 16; std::array<_Tp, _Nm>::value_type = unsigned char]’
   63 |   res.fill(0);
      |   ~~~~~~~~^~~

https://github.com/facebookincubator/Glean/runs/7550852020?check_suite_focus=true#step:15:540

I think we need some eyes on this as afaik folly won't build on stock github CI linux vms with gcc or clang due to this.

[donsbot]

Tentatively looks fixed by 8fcb145f659f2b2a70295bc979c164ed825fe8b2

[donsbot]

Nope, still borked on some variants.

The CXX compiler identification is Clang 12.0.1, https://github.com/donsbot/Glean/runs/7622200685?check_suite_focus=true#step:14:830

[348/901] Building CXX object CMakeFiles/base64_detail_test.dir/folly/detail/base64_detail/tests/Base64PlatformTest.cpp.o
FAILED: CMakeFiles/base64_detail_test.dir/folly/detail/base64_detail/tests/Base64PlatformTest.cpp.o 
/usr/bin/c++ -DBOOST_ALL_NO_LIB -DBOOST_ATOMIC_DYN_LINK -DBOOST_CONTEXT_DYN_LINK -DBOOST_FILESYSTEM_DYN_LINK -DBOOST_PROGRAM_OPTIONS_DYN_LINK -DBOOST_REGEX_DYN_LINK -DBOOST_SYSTEM_DYN_LINK -DBOOST_THREAD_DYN_LINK -DFMT_LOCALE -DFMT_SHARED -DFOLLY_XLOG_STRIP_PREFIXES=\"/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git:/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/build/folly\" -DGFLAGS_IS_A_DLL=0 -D_GNU_SOURCE -D_REENTRANT -I/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git -I/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/build/folly -I/usr/include/libiberty -isystem /github/home/.hsthrift/include -march=corei7 -fsized-deallocation -O2 -g -DNDEBUG -g -std=gnu++1z -finput-charset=UTF-8 -fsigned-char -Wall -Wno-deprecated -Wno-deprecated-declarations -Wno-sign-compare -Wno-unused -Wuninitialized -Wunused-label -Wunused-result -Wno-noexcept-type -Wno-nullability-completeness -Wno-inconsistent-missing-override -faligned-new -fopenmp -DGTEST_HAS_PTHREAD=1 -std=gnu++17 -MD -MT CMakeFiles/base64_detail_test.dir/folly/detail/base64_detail/tests/Base64PlatformTest.cpp.o -MF CMakeFiles/base64_detail_test.dir/folly/detail/base64_detail/tests/Base64PlatformTest.cpp.o.d -o CMakeFiles/base64_detail_test.dir/folly/detail/base64_detail/tests/Base64PlatformTest.cpp.o -c /tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git/folly/detail/base64_detail/tests/Base64PlatformTest.cpp
/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git/folly/detail/base64_detail/tests/Base64PlatformTest.cpp:60:40: error: constexpr function never produces a constant expression [-Winvalid-constexpr]
constexpr std::array<std::uint8_t, 16> expectedPackIndexesToBytes(
                                       ^
/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git/folly/detail/base64_detail/tests/Base64PlatformTest.cpp:63:7: note: non-constexpr function 'fill' cannot be used in a constant expression
  res.fill(0);
      ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/array:117:7: note: declared here
      fill(const value_type& __u)
      ^
1 error generated.

[donsbot]

And gcc 9: - The CXX compiler identification is GNU 9.4.0

/tmp/fbcode_builder_getdeps-Z__wZGleanZGleanZhsthriftZbuildZfbcode_builder-root/repos/github.com-facebook-folly.git/folly/detail/base64_detail/tests/Base64PlatformTest.cpp:63:11: error: call to non-‘constexpr’ function ‘void std::array<_Tp, _Nm>::fill(const value_type&) [with _Tp = unsigned char; long unsigned int _Nm = 16; std::array<_Tp, _Nm>::value_type = unsigned char]’
   63 |   res.fill(0);
      |   ~~~~~~~~^~~

[donsbot]

the folly linux CI step is failing with same reasons, btw. https://github.com/facebook/folly/runs/7400055532?check_suite_focus=true (as are downstream dependencies).

[DenisYaroshevskiy]

@donsbot - I believe that specific issue is solved. Can we check again? I unfortunately don't know how to reproduce this locally.

[donsbot]

Yep! Looks solved. Thanks for pushing!

The folly Linux CI is still red though, as there's another build error that crept in while this one was active.

/home/runner/work/folly/folly/folly/concurrency/test/ThreadCachedSynchronizedBench.cpp: In function ‘void read_int_atomic(unsigned int)’:
/home/runner/work/folly/folly/folly/concurrency/test/ThreadCachedSynchronizedBench.cpp:55:30: error: class template argument deduction failed:
   folly::relaxed_atomic obj{3};
                              ^

[Yejy813]

meet the same problem， g++ (GCC) 8.5.0 . CentOS Linux release 8.5.2111

[DenisYaroshevskiy]

meet the same problem， g++ (GCC) 8.5.0 . CentOS Linux release 8.5.2111

Can you clarify - which same problem? Can you share the error message? The static_assert was rewritten sometime back. Same as CTAD.

What's the issue in question?

[Yejy813]

meet the same problem， g++ (GCC) 8.5.0 . CentOS Linux release 8.5.2111

Can you clarify - which same problem? Can you share the error message? The static_assert was rewritten sometime back. Same as CTAD.

What's the issue in question?

This is error screenshot.

I commented out this part of the code and then compiled it normally.

[Yejy813]

meet the same problem， g++ (GCC) 8.5.0 . CentOS Linux release 8.5.2111

Can you clarify - which same problem? Can you share the error message? The static_assert was rewritten sometime back. Same as CTAD.

What's the issue in question?

sry. maybe wrong reply issue. hhhh