Can not compile when using clang with cmake and -DWITH_STL=ON

[owent]

Describe your environment

OS: Ubuntu 22.04
Compiler: Clang 14 with -stdlib=libc++
Otel-cpp version: v1.8.1

Steps to reproduce
Describe exactly how to reproduce the error. Include a code sample if applicable.

What is the expected behavior?
Compiling success.

What is the actual behavior?

 [ 35%] Building CXX object sdk/src/trace/CMakeFiles/opentelemetry_trace.dir/samplers/always_on_factory.cc.o
In file included from /home/runner/work/cmake-toolset/cmake-toolset/test/third_party/packages/opentelemetry-cpp-v1.8.1/sdk/src/trace/simple_processor_factory.cc:5:
/home/runner/work/cmake-toolset/cmake-toolset/test/third_party/packages/opentelemetry-cpp-v1.8.1/sdk/include/opentelemetry/sdk/trace/simple_processor.h:76:38: warning: macro 'ATOMIC_FLAG_INIT' has been marked as deprecated [-Wdeprecated-pragma]
  std::atomic_flag shutdown_latch_ = ATOMIC_FLAG_INIT;
                                     ^
/usr/lib/llvm-14/bin/../include/c++/v1/atomic:2712:44: note: macro marked 'deprecated' here
#  pragma clang deprecated(ATOMIC_FLAG_INIT)

/home/runner/work/cmake-toolset/cmake-toolset/test/third_party/packages/opentelemetry-cpp-v1.8.1/sdk/src/metrics/meter_context.cc:48:10: error: no matching constructor for initialization of 'nostd::span<std::shared_ptr<Meter>>' (aka 'span<std::shared_ptr<opentelemetry::sdk::metrics::Meter>, 18446744073709551615UL>')
  return nostd::span<std::shared_ptr<Meter>>{meters_};
         ^                                  ~~~~~~~~~
/usr/lib/llvm-14/bin/../include/c++/v1/span:401:15: note: candidate constructor not viable: no known conversion from 'std::vector<std::shared_ptr<Meter>>' to 'const std::span<std::shared_ptr<opentelemetry::sdk::metrics::Meter>, 18446744073709551615>' for 1st argument
    constexpr span           (const span&) noexcept = default;
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:425:15: note: candidate template ignored: could not match 'type_identity_t<std::span<std::shared_ptr<opentelemetry::sdk::metrics::Meter>, 18446744073709551615>::element_type>[_Sz]' (aka 'std::shared_ptr<opentelemetry::sdk::metrics::Meter>[_Sz]') against 'std::vector<std::shared_ptr<Meter>>'
    constexpr span(type_identity_t<element_type> (&__arr)[_Sz]) noexcept : __data{__arr}, __size{_Sz} {}
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:430:15: note: candidate template ignored: could not match 'array' against 'vector'
    constexpr span(array<_OtherElementType, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {}
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:435:15: note: candidate template ignored: could not match 'array' against 'vector'
    constexpr span(const array<_OtherElementType, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {}
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:445:19: note: candidate template ignored: could not match 'span' against 'vector'
        constexpr span(const span<_OtherElementType, _OtherExtent>& __other,
                  ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:399:41: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
    _LIBCPP_INLINE_VISIBILITY constexpr span() noexcept : __data{nullptr}, __size{0} {}
                                        ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:410:15: note: candidate constructor template not viable: requires 2 arguments, but 1 was provided
    constexpr span(_It __first, size_type __count)
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:419:15: note: candidate constructor template not viable: requires 2 arguments, but 1 was provided
    constexpr span(_It __first, _End __last)
              ^
/home/runner/work/cmake-toolset/cmake-toolset/test/third_party/packages/opentelemetry-cpp-v1.8.1/sdk/src/metrics/meter_context.cc:53:10: error: no matching conversion for functional-style cast from 'std::vector<std::shared_ptr<CollectorHandle>>' to 'nostd::span<std::shared_ptr<CollectorHandle>>' (aka 'span<std::shared_ptr<opentelemetry::sdk::metrics::CollectorHandle>, 18446744073709551615UL>')
  return nostd::span<std::shared_ptr<CollectorHandle>>(collectors_);
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/llvm-14/bin/../include/c++/v1/span:401:15: note: candidate constructor not viable: no known conversion from 'std::vector<std::shared_ptr<CollectorHandle>>' to 'const std::span<std::shared_ptr<opentelemetry::sdk::metrics::CollectorHandle>, 18446744073709551615>' for 1st argument
    constexpr span           (const span&) noexcept = default;
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:425:15: note: candidate template ignored: could not match 'type_identity_t<std::span<std::shared_ptr<opentelemetry::sdk::metrics::CollectorHandle>, 18446744073709551615>::element_type>[_Sz]' (aka 'std::shared_ptr<opentelemetry::sdk::metrics::CollectorHandle>[_Sz]') against 'std::vector<std::shared_ptr<CollectorHandle>>'
    constexpr span(type_identity_t<element_type> (&__arr)[_Sz]) noexcept : __data{__arr}, __size{_Sz} {}
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:430:15: note: candidate template ignored: could not match 'array' against 'vector'
    constexpr span(array<_OtherElementType, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {}
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:435:15: note: candidate template ignored: could not match 'array' against 'vector'
    constexpr span(const array<_OtherElementType, _Sz>& __arr) noexcept : __data{__arr.data()}, __size{_Sz} {}
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:445:19: note: candidate template ignored: could not match 'span' against 'vector'
        constexpr span(const span<_OtherElementType, _OtherExtent>& __other,
                  ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:399:41: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
    _LIBCPP_INLINE_VISIBILITY constexpr span() noexcept : __data{nullptr}, __size{0} {}
                                        ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:410:15: note: candidate constructor template not viable: requires 2 arguments, but 1 was provided
    constexpr span(_It __first, size_type __count)
              ^
/usr/lib/llvm-14/bin/../include/c++/v1/span:419:15: note: candidate constructor template not viable: requires 2 arguments, but 1 was provided
    constexpr span(_It __first, _End __last)
              ^
[ 28%] Building CXX object sdk/src/trace/CMakeFiles/opentelemetry_trace.dir/tracer_context_factory.cc.o
1 warning and 2 errors generated.
gmake[2]: *** [sdk/src/metrics/CMakeFiles/opentelemetry_metrics.dir/build.make:118: sdk/src/metrics/CMakeFiles/opentelemetry_metrics.dir/meter_context.cc.o] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:526: sdk/src/metrics/CMakeFiles/opentelemetry_metrics.dir/all] Error 2
gmake[1]: *** Waiting for unfinished jobs....
[ 29%] Building CXX object sdk/src/trace/CMakeFiles/opentelemetry_trace.dir/tracer_provider.cc.o

[marcalff]

Please take a look at:

Fix OTELCPP_MAINTAINER_MODE #1844

It builds with CLang 14, using CMake, using WITH_STL=ON.

[owent]

Please take a look at:

Fix OTELCPP_MAINTAINER_MODE #1844

It builds with CLang 14, using CMake, using WITH_STL=ON.

I don't find -DWITH_STL=ON in cmake.maintainer.test of #1844 , and it do not use libc++ .
In my understanding, most clang on Linux do not compile with -DCLANG_DEFAULT_CXX_STDLIB=libc++ and will use libstdc++ by default.

[marcalff]

Sorry, I thought cmake.maintainer.test was using WITH_STL=ON, but it turns out it does not.

Still, PR #1844 fixes some warnings related to nostd::span, and uses GOOGLETEST_VERSION as well, so there is some overlap here.

[owent]

Sorry, I thought cmake.maintainer.test was using WITH_STL=ON, but it turns out it does not.

Still, PR #1844 fixes some warnings related to nostd::span, and uses GOOGLETEST_VERSION as well, so there is some overlap here.

I will merge #1844 into #1851 later.

Do you think we can upgrade the default version of googletest ? 1.10.0 use -Werror but 1.12.1 do not, and it may lead to more compiling error in the future if we built otlp-cpp on a new compiler in the future.

[owent]

Sorry, I thought cmake.maintainer.test was using WITH_STL=ON, but it turns out it does not.
Still, PR #1844 fixes some warnings related to nostd::span, and uses GOOGLETEST_VERSION as well, so there is some overlap here.

I will merge #1844 into #1851 later.

Do you think we can upgrade the default version of googletest ? 1.10.0 use -Werror but 1.12.1 do not, and it may lead to more compiling error in the future if we built otlp-cpp on a new compiler in the future.

#1851 has merged the changes from #1844 now.