Merge branch 'main' into fix-msvc-library-selection

.github/workflows/ci.yml

@@ -29,25 +29,26 @@ jobs:
         ./ci/do_ci.sh cmake.test
 
   cmake_gcc_maintainer_sync_test:
-    name: CMake gcc 13 (maintainer mode, sync)
-    runs-on: ubuntu-latest
+    name: CMake gcc 14 (maintainer mode, sync)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
         PROTOBUF_VERSION: 21.12
       run: |
+        sudo apt remove needrestart #refer: https://github.com/actions/runner-images/issues/9937
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake gcc (maintainer mode, sync)
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
       run: |
         ./ci/do_ci.sh cmake.maintainer.sync.test
     - name: generate test cert
@@ -61,25 +62,26 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_gcc_maintainer_async_test:
-    name: CMake gcc 13 (maintainer mode, async)
-    runs-on: ubuntu-latest
+    name: CMake gcc 14 (maintainer mode, async)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
         PROTOBUF_VERSION: 21.12
       run: |
+        sudo apt remove needrestart #refer: https://github.com/actions/runner-images/issues/9937
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake gcc (maintainer mode, async)
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
       run: |
         ./ci/do_ci.sh cmake.maintainer.async.test
     - name: generate test cert
@@ -93,25 +95,26 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_clang_maintainer_sync_test:
-    name: CMake clang 15 (maintainer mode, sync)
-    runs-on: ubuntu-latest
+    name: CMake clang 18 (maintainer mode, sync)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
         PROTOBUF_VERSION: 21.12
       run: |
+        sudo apt remove needrestart #refer: https://github.com/actions/runner-images/issues/9937
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake clang (maintainer mode, sync)
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
       run: |
         ./ci/do_ci.sh cmake.maintainer.sync.test
     - name: generate test cert
@@ -125,25 +128,26 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_clang_maintainer_async_test:
-    name: CMake clang 15 (maintainer mode, async)
-    runs-on: ubuntu-latest
+    name: CMake clang 18 (maintainer mode, async)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
         PROTOBUF_VERSION: 21.12
       run: |
+        sudo apt remove needrestart #refer: https://github.com/actions/runner-images/issues/9937
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake clang (maintainer mode, async)
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
       run: |
         ./ci/do_ci.sh cmake.maintainer.async.test
     - name: generate test cert
@@ -157,25 +161,26 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_clang_maintainer_abiv2_test:
-    name: CMake clang 15 (maintainer mode, abiv2)
-    runs-on: ubuntu-latest
+    name: CMake clang 18 (maintainer mode, abiv2)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
         PROTOBUF_VERSION: 21.12
       run: |
+        sudo apt remove needrestart #refer: https://github.com/actions/runner-images/issues/9937
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake clang (maintainer mode, abiv2)
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
       run: |
         ./ci/do_ci.sh cmake.maintainer.abiv2.test
     - name: generate test cert
@@ -726,11 +731,11 @@ jobs:
 
   format:
     name: Format
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
     - name: setup
-      run: sudo ./ci/install_format_tools.sh
+      run: sudo apt remove needrestart && sudo ./ci/install_format_tools.sh #refer: https://github.com/actions/runner-images/issues/9937
     - name: run tests
       run: ./ci/do_ci.sh format
 

.github/workflows/iwyu.yml

@@ -0,0 +1,60 @@
+
+name: include-what-you-use
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  iwyu:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: 'recursive'
+
+      - name: setup dependencies
+        run: |
+          sudo apt update -y
+          sudo apt install -y --no-install-recommends --no-install-suggests \
+            build-essential \
+            iwyu \
+            cmake \
+            ninja-build \
+            libssl-dev \
+            libcurl4-openssl-dev \
+            libprotobuf-dev \
+            protobuf-compiler \
+            libgmock-dev \
+            libgtest-dev \
+            libbenchmark-dev
+
+      - name: Prepare CMake
+        run: |
+          TOPDIR=`pwd`
+          mkdir build && cd build
+          CC="clang" CXX="clang++" cmake \
+            -DCMAKE_CXX_INCLUDE_WHAT_YOU_USE="include-what-you-use;-w;-Xiwyu;--mapping_file=${TOPDIR}/.iwyu.imp;" \
+            -DBUILD_TESTING=OFF \
+            -DBUILD_W3CTRACECONTEXT_TEST=OFF \
+            ..
+
+      - name: iwyu_tool
+        run: |
+          cd build
+          make -k 2>&1 | tee -a iwyu.log
+
+      - uses: actions/upload-artifact@v4
+        if: success() || failure()
+        with:
+          name: Logs (include-what-you-use)
+          path: ./build/*.log
+
+      - name: count warnings
+        run: |
+          cd build
+          COUNT=`grep -c "Warning:" iwyu.log`
+          echo "include-what-you-use reported ${COUNT} warning(s)"
+

.iwyu.imp

@@ -0,0 +1,13 @@
+# Copyright The OpenTelemetry Authors
+# SPDX-License-Identifier: Apache-2.0
+
+# include-what-you-use mapping file
+
+[
+  # Work around for C++ STL
+  { "include": ["<bits/chrono.h>", "private", "<chrono>", "public"] },
+
+  # Local opentelemetry-cpp
+
+]
+

CHANGELOG.md

@@ -18,6 +18,63 @@ Increment the:
 * [SDK] Update ExemplarFilter and ExemplarReservoir for spec
   [#2372](https://github.com/open-telemetry/opentelemetry-cpp/pull/2372)
 
+* [CI] Upgrade to clang-format 18
+  [#2684](https://github.com/open-telemetry/opentelemetry-cpp/pull/2684)
+
+* [API/SDK] Provider cleanup
+  [#2664](https://github.com/open-telemetry/opentelemetry-cpp/pull/2664)
+
+Important changes:
+
+* [API/SDK] Provider cleanup
+  [#2664](https://github.com/open-telemetry/opentelemetry-cpp/pull/2664)
+  * Before this fix:
+    * The API class `opentelemetry::trace::Tracer` exposed methods such
+      as `ForceFlush()`, `ForceFlushWithMicroseconds()`, `Close()`
+      and `CloseWithMicroseconds()`.
+    * These methods are meant to be used when configuring the SDK,
+      and should not be part of the API. Exposing them was an oversight.
+    * Two of these methods are virtual, and therefore part of the ABI.
+  * After this fix:
+    * In `OPENTELEMETRY_ABI_VERSION_NO 1`, nothing is changed,
+      because removing this code would break the ABI.
+    * In `OPENTELEMETRY_ABI_VERSION_NO 2`, these methods are moved
+      from the API to the SDK. This is a breaking change for ABI version 2,
+      which is still experimental.
+  * In all cases, instrumenting an application should not
+    invoke flush or close on a tracer, do not use these methods.
+
+Breaking changes:
+
+* [API/SDK] Provider cleanup
+  [#2664](https://github.com/open-telemetry/opentelemetry-cpp/pull/2664)
+  * Before this fix:
+    * SDK factory methods such as:
+      * opentelemetry::sdk::trace::TracerProviderFactory::Create()
+      * opentelemetry::sdk::metrics::MeterProviderFactory::Create()
+      * opentelemetry::sdk::logs::LoggerProviderFactory::Create()
+      * opentelemetry::sdk::logs::EventLoggerProviderFactory::Create()
+      returned an API object (opentelemetry::trace::TracerProvider)
+      to the caller.
+  * After this fix, these methods return an SDK level object
+    (opentelemetry::sdk::trace::TracerProvider) to the caller.
+  * Returning an SDK object is necessary for the application to
+    cleanup and invoke SDK level methods, such as ForceFlush(),
+    on a provider.
+  * The application code that configures the SDK, by calling
+    the various provider factories, may need adjustment.
+  * All the examples have been updated, and in particular no
+    longer perform static_cast do convert an API object to an SDK object.
+    Please refer to examples for guidance on how to adjust.
+  * If adjusting application code is impractical,
+    an alternate and temporary solution is to build with option
+    WITH_DEPRECATED_SDK_FACTORY=ON in CMake.
+  * Option WITH_DEPRECATED_SDK_FACTORY=ON will allow to build code
+    without application changes, posponing changes for later.
+  * WITH_DEPRECATED_SDK_FACTORY=ON is temporary, only to provide
+    an easier migration path. Expect this flag to be removed,
+    as early as by the next release.
+
 Notes on experimental features:
 
 * [#2372](https://github.com/open-telemetry/opentelemetry-cpp/issues/2372)

CMakeLists.txt

@@ -159,6 +159,14 @@ message(STATUS "OPENTELEMETRY_VERSION=${OPENTELEMETRY_VERSION}")
 
 option(WITH_NO_DEPRECATED_CODE "Do not include deprecated code" OFF)
 
+# This option is temporary, and will be removed. Set
+# WITH_DEPRECATED_SDK_FACTORY=OFF to migrate to the new SDK code.
+option(WITH_DEPRECATED_SDK_FACTORY "Use deprecated SDK provider factory" ON)
+
+if(WITH_DEPRECATED_SDK_FACTORY)
+  message(WARNING "WITH_DEPRECATED_SDK_FACTORY=ON is temporary and deprecated")
+endif()
+
 set(WITH_STL
     "OFF"
     CACHE STRING "Which version of the Standard Library for C++ to use")