Need advice for building

[darix]

I am preparing all the packages to enable otel support in the opensuse haproxy package. Thank you for working on this!

but the build fails with:
https://build.opensuse.org/public/build/home:darix:apps/openSUSE_Tumbleweed/x86_64/opentelemetry-c-wrapper/_log

[zaga00]

Hello @darix,

I see two problems here, the first is caused by the use of typeof() in the C++ source code, which can be used if the compiler option -std=gnu++17 is used, however you use -std=c++17 - this is solved by the last commit in the 'main' branch ("BUILD: Replaced GCC typeof with decltype/__typeof__").

The second problem is that you did not apply the set of patches for opentelemetry C++ library that is in the scripts/build directory - unfortunately, opentelemetry C++ library does not support starting all threads in advance, and that is why the set of patches in question is needed.

That second problem would be solved more elegantly if they were accepted into the upstream repository, but I haven't found the time for that yet.

[darix]

I will backport that commit into the package.

i saw those patches but the question for me as a packager is. can i enable them savely in our opentelemetry-cpp package in the distro or might that break other software? are there any plans to upstream those patches?

[zaga00]

Apart from the first patch, which you should not use (0001-opentelemetry-cpp-1.26.0.patch), I think the rest is harmless because in order to activate threads in advance, you need to use these additional calls, which is not done by default.

I meant to send it upstream once, but I haven't got around to it yet, because I have other things to do (for example, enable the use of multiple otel filters within haproxy).

[darix]

well I applied them in my devel place for now. but yeah upstreaming them would definitely be appreciated :)

[darix]

JFYI one last issue remaining. this is building with a patched otel-cpp https://build.opensuse.org/public/build/home:darix:apps/openSUSE_Tumbleweed/x86_64/opentelemetry-c-wrapper/_log

[zaga00]

I think you are missing the cmake option -DWITH_ASYNC_EXPORT_PREVIEW=ON when building the opentelemetry cpp package.

[darix]

using the cmake build. the following libraries are not linked:

/usr/lib64/libopentelemetry_common.so
/usr/lib64/libopentelemetry_trace.so
/usr/lib64/libopentelemetry_metrics.so
/usr/lib64/libopentelemetry_logs.so
/usr/lib64/libopentelemetry_resources.so

after adding those the linking leaves me with this warning:

In member function ‘__ct ’,
    inlined from ‘__ct ’ at /usr/include/opentelemetry/trace/trace_state.h:236:79,
    inlined from ‘Set’ at /usr/include/opentelemetry/trace/trace_state.h:152:66,
    inlined from ‘otel_span_context_trace_state_set’ at /home/abuild/rpmbuild/BUILD/opentelemetry-c-wrapper-1.0.2-build/opentelemetry-c-wrapper-1.0.2/src/span.cpp:1872:41:
/usr/include/opentelemetry/common/kv_properties.h:209:73: warning: argument 1 value ‘18446744073709551615’ exceeds maximum object size 9223372036854775807 [[-Walloc-size-larger-than=](https://gcc.gnu.org/onlinedocs/gcc-15.2.0/gcc/Warning-Options.html#index-Walloc-size-larger-than_003d)]
  209 |       : num_entries_(0), max_num_entries_(size), entries_(new Entry[size])
      |                                                                         ^
/usr/include/c++/15/new: In function ‘otel_span_context_trace_state_set’:
/usr/include/c++/15/new:140:26: note: in a call to allocation function ‘operator new []’ declared here
  140 | _GLIBCXX_NODISCARD void* operator new[](std::size_t)
      |                          ^

looks like 866fd3f already fixes that?

well almost. needs this patch on top:

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0936162..3b5ae89 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -436,7 +436,6 @@ set(SDK_LIBRARIES       "")
 set(SYSLIB_LIBRARIES    "")
 set(SYSLIB_LIBRARY_DIRS "")

-if(BUILD_STATIC)
     message(STATUS "Probing OpenTelemetry SDK libraries:")

     macro(probe_sdk_lib _lib)
@@ -484,6 +483,7 @@ if(BUILD_STATIC)
     probe_sdk_lib(opentelemetry_configuration)
     probe_sdk_lib(opentelemetry_version)

+if(BUILD_STATIC)
     ## System libraries that OTel SDK components depend on (protobuf, curl,
     ## gRPC).  Use non-static pkg-config --libs so the linker picks up shared
     ## libraries that resolve their own transitive deps at runtime (avoids

working package now at https://build.opensuse.org/package/show/home:darix:apps/opentelemetry-c-wrapper

[zaga00]

For the warning you noticed, I added commit 9519c3a.

cmake is not the recommended way to configure the wrapper library, so it is possible that it contains some flaws (it was added for completeness) - I will note your change.

Thank you for reporting the problems and helping to resolve them.