Require C++20 (#13904)

Summary:
I am wanting to use std::counting_semaphore for something and the timing seems good to require C++20 support. The internets suggest:

* GCC >= 10 is adequate, >= 11 preferred
* Clang >= 10 is needed
* Visual Studio >= 2019 is adquate

And popular linux distributions look like this:
* CentOS Stream 9 -> GCC 11.2  (CentOS 8 is EOL)
* Ubuntu 22.04 LTS -> GCC 11.x  (Ubuntu 20 just ended standard support)
* Debian 12 (oldstable) -> GCC 12.2
  * (Debian 11 has ended security updates, uses GCC 10.2)

This required generating a new docker image based on Ubuntu 22 for CI using gcc. The existing Ubuntu 20 image works for covering appropriate clang versions (though we should maybe add a much later version as well, in the next increment of our Ubuntu 22 image; however the minimum available clang build from apt.llvm.org for Ubuntu 22 is clang 13).

Update to SetDumpFilter is to quiet a mysterious gcc-13 warning-as-error.

Removed --compile-no-warning-as-error from a cmake command line because cmake in the new docker image is too old for this option.

Pull Request resolved: #13904

Test Plan: CI, one minor unit test added to verify std::counting_semaphor works

Reviewed By: xingbowang

Differential Revision: D81266435

Pulled By: pdillinger

fbshipit-source-id: 26040eeccca7004416e29a6ff4f6ea93f2052684

Author: pdillinger

.github/workflows/nightly.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -32,7 +32,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     env:
       TEST_TMPDIR: "/tmp/rocksdb_test_tmp"
@@ -63,7 +63,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -94,7 +94,7 @@ jobs:
     runs-on:
       labels: 4-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -117,28 +117,13 @@ jobs:
     - name: Build fuzzers
       run: cd fuzz && make sst_file_writer_fuzzer db_fuzzer db_map_fuzzer
     - uses: "./.github/actions/post-steps"
-  build-linux-gcc-11-no_test_run:
-    if: ${{ github.repository_owner == 'facebook' }}
-    runs-on:
-      labels: 16-core-ubuntu
-    container:
-      image: zjay437/rocksdb:0.6
-      options: --shm-size=16gb
-    steps:
-    - uses: actions/[email protected]
-    - uses: "./.github/actions/pre-steps"
-    - run: LIB_MODE=static CC=gcc-11 CXX=g++-11 V=1 make -j32 all microbench
-    - uses: "./.github/actions/post-steps"
   build-linux-cmake-with-folly-lite-no-test:
     if: ${{ github.repository_owner == 'facebook' }}
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
-    env:
-      CC: gcc-10
-      CXX: g++-10
     steps:
     - uses: actions/[email protected]
     - uses: "./.github/actions/pre-steps"

.github/workflows/pr-jobs.yml

@@ -66,7 +66,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -78,7 +78,7 @@ jobs:
     runs-on:
       labels: 4-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -97,11 +97,8 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
-    env:
-      CC: gcc-10
-      CXX: g++-10
     steps:
     - uses: actions/[email protected]
     - uses: "./.github/actions/pre-steps"
@@ -114,11 +111,8 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
-    env:
-      CC: gcc-10
-      CXX: g++-10
     steps:
     - uses: actions/[email protected]
     - uses: "./.github/actions/pre-steps"
@@ -131,11 +125,8 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
-    env:
-      CC: gcc-10
-      CXX: g++-10
     steps:
     - uses: actions/[email protected]
     - uses: "./.github/actions/pre-steps"
@@ -147,11 +138,8 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
-    env:
-      CC: gcc-10
-      CXX: g++-10
     steps:
     - uses: actions/[email protected]
     - uses: "./.github/actions/pre-steps"
@@ -164,7 +152,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -176,7 +164,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -190,7 +178,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -236,29 +224,17 @@ jobs:
     - run: make clean
     - run: CC=clang-13 CXX=clang++-13 USE_CLANG=1 DEBUG_LEVEL=0 make -j32 release
     - uses: "./.github/actions/post-steps"
-  build-linux-gcc-8-no_test_run:
+  build-linux-gcc-13-no_test_run:
     if: ${{ github.repository_owner == 'facebook' }}
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
     - uses: "./.github/actions/pre-steps"
-    - run: CC=gcc-8 CXX=g++-8 V=1 make -j32 all
-    - uses: "./.github/actions/post-steps"
-  build-linux-gcc-10-cxx20-no_test_run:
-    if: ${{ github.repository_owner == 'facebook' }}
-    runs-on:
-      labels: 16-core-ubuntu
-    container:
-      image: zjay437/rocksdb:0.6
-      options: --shm-size=16gb
-    steps:
-    - uses: actions/[email protected]
-    - uses: "./.github/actions/pre-steps"
-    - run: CC=gcc-10 CXX=g++-10 V=1 ROCKSDB_CXX_STANDARD=c++20 make -j32 all
+    - run: CC=gcc-13 CXX=g++-13 V=1 make -j32 all microbench
     - uses: "./.github/actions/post-steps"
 
   # ======================== Linux Other Checks ======================= #
@@ -300,7 +276,7 @@ jobs:
     runs-on:
       labels: 4-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -337,7 +313,7 @@ jobs:
     runs-on:
       labels: 16-core-ubuntu
     container:
-      image: zjay437/rocksdb:0.6
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     - uses: actions/[email protected]
@@ -404,11 +380,13 @@ jobs:
     runs-on:
       labels: 4-core-ubuntu
     container:
-      image: evolvedbinary/rocksjava:centos7_x64-be
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     # The docker image is intentionally based on an OS that has an older GLIBC version.
     # That GLIBC is incompatibile with GitHub's actions/checkout. Thus we implement a manual checkout step.
+    # NOTE: replaced evolvedbinary/rocksjava:centos7_x64-be with ghcr.io/facebook/rocksdb_ubuntu:22.0
+    # until a more appropriate docker image with C++20 support is made.
     - name: Checkout
       env:
         GH_TOKEN: ${{ github.token }}
@@ -425,18 +403,21 @@ jobs:
         which java && java -version
         which javac && javac -version
     - name: Test RocksDBJava
-      run: scl enable devtoolset-7 'make V=1 J=8 -j8 jtest'
-    # NOTE: post-steps skipped because of compatibility issues with docker image
+    # NOTE: replaced scl enable devtoolset-7 'make V=1 J=8 -j8 jtest'
+      run: make V=1 J=8 -j8 jtest
+    # post-steps skipped because of compatibility issues with docker image
   build-linux-java-static:
     if: ${{ github.repository_owner == 'facebook' }}
     runs-on:
       labels: 4-core-ubuntu
     container:
-      image: evolvedbinary/rocksjava:centos7_x64-be
+      image: ghcr.io/facebook/rocksdb_ubuntu:22.0
       options: --shm-size=16gb
     steps:
     # The docker image is intentionally based on an OS that has an older GLIBC version.
     # That GLIBC is incompatibile with GitHub's actions/checkout. Thus we implement a manual checkout step.
+    # NOTE: replaced evolvedbinary/rocksjava:centos7_x64-be with ghcr.io/facebook/rocksdb_ubuntu:22.0
+    # until a more appropriate docker image with C++20 support is made.
     - name: Checkout
       env:
         GH_TOKEN: ${{ github.token }}
@@ -453,8 +434,9 @@ jobs:
         which java && java -version
         which javac && javac -version
     - name: Build RocksDBJava Static Library
-      run: scl enable devtoolset-7 'make V=1 J=8 -j8 rocksdbjavastatic'
-    # NOTE: post-steps skipped because of compatibility issues with docker image
+    # NOTE: replaced scl enable devtoolset-7 'make V=1 J=8 -j8 rocksdbjavastatic'
+      run: make V=1 J=8 -j8 rocksdbjavastatic
+    # post-steps skipped because of compatibility issues with docker image
   build-macos-java:
     if: ${{ github.repository_owner == 'facebook' }}
     runs-on: macos-13

CMakeLists.txt

@@ -27,7 +27,7 @@
 #
 # Linux:
 #
-# 1. Install a recent toolchain if you're on a older distro. C++17 required (GCC >= 7, Clang >= 5)
+# 1. Install a recent toolchain if you're on a older distro. C++20 required (GCC >= 11, Clang >= 10)
 # 2. mkdir build; cd build
 # 3. cmake ..
 # 4. make -j
@@ -100,7 +100,7 @@ endif()
 option(ROCKSDB_BUILD_SHARED "Build shared versions of the RocksDB libraries" ON)
 
 if( NOT DEFINED CMAKE_CXX_STANDARD )
-  set(CMAKE_CXX_STANDARD 17)
+  set(CMAKE_CXX_STANDARD 20)
 endif()
 
 include(CMakeDependentOption)
@@ -314,7 +314,6 @@ endif()
 
 # Check if -latomic is required or not
 if (NOT MSVC)
-  set(CMAKE_REQUIRED_FLAGS "--std=c++17")
   CHECK_CXX_SOURCE_COMPILES("
 #include <atomic>
 std::atomic<uint64_t> x(0);

INSTALL.md

@@ -6,7 +6,7 @@ than release mode.
 
 RocksDB's library should be able to compile without any dependency installed,
 although we recommend installing some compression libraries (see below).
-We do depend on newer gcc/clang with C++17 support (GCC >= 7, Clang >= 5).
+We do depend on newer gcc/clang with C++20 support (GCC >= 11, Clang >= 10).
 
 There are few options when compiling RocksDB:
 
@@ -60,7 +60,7 @@ most processors made since roughly 2013.
 ## Supported platforms
 
 * **Linux - Ubuntu**
-    * Upgrade your gcc to version at least 7 to get C++17 support.
+    * Upgrade your gcc to version at least 11 to get C++20 support.
     * Install gflags. First, try: `sudo apt-get install libgflags-dev`
       If this doesn't work and you're using Ubuntu, here's a nice tutorial:
       (http://askubuntu.com/questions/312173/installing-gflags-12-04)
@@ -72,7 +72,7 @@ most processors made since roughly 2013.
     * Install zstandard: `sudo apt-get install libzstd-dev`.
 
 * **Linux - CentOS / RHEL**
-    * Upgrade your gcc to version at least 7 to get C++17 support
+    * Upgrade your gcc to version at least 11 to get C++20 support
     * Install gflags:
 
               git clone https://github.com/gflags/gflags.git
@@ -122,7 +122,7 @@ most processors made since roughly 2013.
               make && sudo make install
 
 * **OS X**:
-    * Install latest C++ compiler that supports C++ 17:
+    * Install latest C++ compiler that supports C++20:
         * Update XCode:  run `xcode-select --install` (or install it from XCode App's settting).
         * Install via [homebrew](http://brew.sh/).
             * If you're first time developer in MacOS, you still need to run: `xcode-select --install` in your command line.
@@ -213,7 +213,7 @@ most processors made since roughly 2013.
              export PATH=/opt/freeware/bin:$PATH
 
 * **Solaris Sparc**
-    * Install GCC 7 and higher.
+    * Install GCC 11 and higher.
     * Use these environment variables:
 
              export CC=gcc

Makefile

@@ -148,10 +148,8 @@ ifeq ($(USE_COROUTINES), 1)
 	USE_FOLLY = 1
 	# glog/logging.h requires HAVE_CXX11_ATOMIC
 	OPT += -DUSE_COROUTINES -DHAVE_CXX11_ATOMIC
-	ROCKSDB_CXX_STANDARD = c++2a
 	USE_RTTI = 1
 ifneq ($(USE_CLANG), 1)
-	ROCKSDB_CXX_STANDARD = c++20
 	PLATFORM_CXXFLAGS += -fcoroutines
 endif
 endif
@@ -683,7 +681,7 @@ am__v_CCH_1 =
 # user build settings
 %.h.pub: %.h # .h.pub not actually created, so re-checked on each invocation
 	$(AM_V_CCH) cd include/ && echo '#include "$(patsubst include/%,%,$<)"' | \
-	  $(CXX) -I. -DROCKSDB_NAMESPACE=42 -x c++ -c - -o /dev/null
+	  $(CXX) -std=$(or $(ROCKSDB_CXX_STANDARD),c++20) -I. -DROCKSDB_NAMESPACE=42 -x c++ -c - -o /dev/null
 
 check-headers: $(HEADER_OK_FILES)
 
@@ -2251,7 +2249,7 @@ libsnappy.a: snappy-$(SNAPPY_VER).tar.gz
 	-rm -rf snappy-$(SNAPPY_VER)
 	tar xvzf snappy-$(SNAPPY_VER).tar.gz
 	mkdir snappy-$(SNAPPY_VER)/build
-	cd snappy-$(SNAPPY_VER)/build && CFLAGS='$(ARCHFLAG) ${JAVA_STATIC_DEPS_CCFLAGS} ${EXTRA_CFLAGS}' CXXFLAGS='$(ARCHFLAG) ${JAVA_STATIC_DEPS_CXXFLAGS} ${EXTRA_CXXFLAGS}' LDFLAGS='${JAVA_STATIC_DEPS_LDFLAGS} ${EXTRA_LDFLAGS}' cmake -DCMAKE_POSITION_INDEPENDENT_CODE=ON -DSNAPPY_BUILD_BENCHMARKS=OFF -DSNAPPY_BUILD_TESTS=OFF --compile-no-warning-as-error ${PLATFORM_CMAKE_FLAGS} .. && $(MAKE) ${SNAPPY_MAKE_TARGET}
+	cd snappy-$(SNAPPY_VER)/build && CFLAGS='$(ARCHFLAG) ${JAVA_STATIC_DEPS_CCFLAGS} ${EXTRA_CFLAGS}' CXXFLAGS='$(ARCHFLAG) ${JAVA_STATIC_DEPS_CXXFLAGS} ${EXTRA_CXXFLAGS}' LDFLAGS='${JAVA_STATIC_DEPS_LDFLAGS} ${EXTRA_LDFLAGS}' cmake -DCMAKE_POSITION_INDEPENDENT_CODE=ON -DSNAPPY_BUILD_BENCHMARKS=OFF -DSNAPPY_BUILD_TESTS=OFF ${PLATFORM_CMAKE_FLAGS} .. && $(MAKE) ${SNAPPY_MAKE_TARGET}
 	cp snappy-$(SNAPPY_VER)/build/libsnappy.a .
 
 lz4-$(LZ4_VER).tar.gz:

build_tools/build_detect_platform

@@ -45,11 +45,11 @@ if test -z "$OUTPUT"; then
   exit 1
 fi
 
-# we depend on C++17, but should be compatible with newer standards
+# we depend on C++20, but should be compatible with newer standards
 if [ "$ROCKSDB_CXX_STANDARD" ]; then
   PLATFORM_CXXFLAGS="-std=$ROCKSDB_CXX_STANDARD"
 else
-  PLATFORM_CXXFLAGS="-std=c++17"
+  PLATFORM_CXXFLAGS="-std=c++20"
 fi
 
 # we currently depend on POSIX platform