Delete the useless 'noexcept(false)' (#1152)

* Remove unused headers from gsl/pointers

forward is already declared in utility, no need to include algorithm which is relativaly heavy
hash is already declared in memory, no need to bring brand-new header system_error for hash only

* Fix: add missing header <functional> to gsl/pointers due to using less/greater

.github/workflows/cmake/action.yml

@@ -0,0 +1,56 @@
+name: Composite CMake
+inputs:
+  cmake_generator:
+    required: false
+    type: string
+    default: 'Unix Makefiles'
+  cmake_build_type:
+    required: true
+    type: string
+    default: ''
+  cmake_cxx_compiler:
+    required: false 
+    type: string 
+  gsl_cxx_standard:
+    required: true
+    type: number
+  extra_cmake_args:
+    required: false
+    type: string
+    default: ''
+  build_cmd:
+    required: true 
+    type: string 
+    default: 'make'
+  test_cmd:
+    required: false
+    type: string 
+    default: 'make test'
+  shell:
+    required: false 
+    type: string
+    default: 'bash'
+
+
+runs:
+  using: composite
+  steps:
+    - name: Create build directory
+      run: mkdir build
+      shell: ${{ inputs.shell }}
+
+    - name: Configure CMake
+      working-directory: build
+      run: cmake -G "${{ inputs.cmake_generator }}" -DCMAKE_BUILD_TYPE=${{ inputs.cmake_build_type }} -DCMAKE_CXX_COMPILER=${{ inputs.cmake_cxx_compiler }} -DGSL_CXX_STANDARD=${{ inputs.gsl_cxx_standard }} -DCI_TESTING:BOOL=ON -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON -Werror=dev ${{ inputs.extra_cmake_args }} ..
+      shell: ${{ inputs.shell }}
+
+    - name: Build
+      working-directory: build
+      run: ${{ inputs.build_cmd }}
+      shell: ${{ inputs.shell }}
+
+    - name: Test
+      working-directory: build
+      run: ${{ inputs.test_cmd }}
+      shell: ${{ inputs.shell }} 
+

.github/workflows/compilers.yml

@@ -0,0 +1,104 @@
+name: Compiler Integration Tests
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+# These jobs are correlated with the officially supported compilers
+# and toolsets. If you change any versions, please update README.md.
+
+jobs:
+  gcc:
+    strategy:
+      matrix:
+        gcc_version: [ 10, 11, 12 ]
+        build_type: [ Debug, Release ]
+        cxx_version: [ 14, 17, 20, 23 ]
+        exclude:
+          - gcc_version: 10
+            cxx_version: 23
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Run CMake (configure, build, test)
+        uses: ./.github/workflows/cmake
+        with:
+          cmake_build_type: ${{ matrix.build_type }}
+          cmake_cxx_compiler: g++-${{ matrix.gcc_version }}
+          gsl_cxx_standard: ${{ matrix.cxx_version }}
+          
+  clang:
+    strategy:
+      matrix:
+        clang_version: [ 13, 14, 15 ]
+        build_type: [ Debug, Release ]
+        cxx_version: [ 14, 17, 20, 23 ]
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+     
+      - name: Run CMake (configure, build, test)
+        uses: ./.github/workflows/cmake
+        with:
+          cmake_build_type: ${{ matrix.build_type }}
+          cmake_cxx_compiler: clang++-${{ matrix.clang_version }}
+          gsl_cxx_standard: ${{ matrix.cxx_version }}
+
+  xcode:
+    strategy:
+      matrix:
+        xcode_version: [ '14.3.1', '15.4' ]
+        build_type: [ Debug, Release ]
+        cxx_version: [ 14, 17, 20, 23 ]
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: select xcode version
+        run: sudo xcode-select -s /Applications/Xcode_${{ matrix.xcode_version }}.app
+
+      - name: Run CMake (configure, build, test)
+        uses: ./.github/workflows/cmake
+        with:
+          cmake_build_type: ${{ matrix.build_type }}
+          cmake_cxx_compiler: clang++
+          gsl_cxx_standard: ${{ matrix.cxx_version }}
+
+  VisualStudio:
+    strategy:
+      matrix:
+        generator: [ 'Visual Studio 16 2019', 'Visual Studio 17 2022' ]
+        image: [ windows-2019, windows-2022 ]
+        build_type: [ Debug, Release ]
+        extra_args: [ '', '-T ClangCL' ]
+        cxx_version: [ 14, 17, 20, 23 ]
+        exclude:
+          - generator: 'Visual Studio 17 2022'
+            image: windows-2019
+          - generator: 'Visual Studio 16 2019'
+            image: windows-2022
+          - generator: 'Visual Studio 16 2019'
+            cxx_version: 23
+    runs-on: ${{ matrix.image }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: microsoft/setup-msbuild@v2
+
+      - name: Run CMake (configure, build, test)
+        uses: ./.github/workflows/cmake
+        with:
+          cmake_generator: ${{ matrix.generator }}
+          cmake_build_type: ${{ matrix.build_type }}
+          gsl_cxx_standard: ${{ matrix.cxx_version }}
+          extra_cmake_args: ${{ matrix.extra_args }}
+          build_cmd: msbuild GSL.sln
+          test_cmd: ctest . --output-on-failure --no-compress-output
+          shell: pwsh
+

README.md

@@ -86,24 +86,17 @@ This is based on [CppCoreGuidelines semi-specification](https://github.com/isocp
 
 # Quick Start
 ## Supported Compilers / Toolsets
-The GSL officially supports the latest and previous major versions of VS with MSVC & LLVM, GCC, Clang, and XCode with Apple-Clang.
-Within these two major versions, we try to target the latest minor updates / revisions (although this may be affected by
-delays between a toolchain's release and when it becomes widely available for use).
-Below is a table showing the versions currently being tested.
+The GSL officially supports recent major versions of Visual Studio with both MSVC and LLVM, GCC, Clang, and XCode with Apple-Clang.
+For each of these major versions, the GSL officially supports C++14, C++17, C++20, and C++23 (when supported by the compiler).
+Below is a table showing the versions currently being tested (also see [.github/workflows/compilers.yml](the workflow).)
 
 Compiler |Toolset Versions Currently Tested
 :------- |--:
- XCode | 13.2.1 & 12.5.1
- GCC | 11[^1] & 10[^2]
- Clang | 12[^2] & 11[^2]
- Visual Studio with MSVC | VS2022[^3] & VS2019[^4]
- Visual Studio with LLVM | VS2022[^3] & VS2019[^4]
-
-
-[^1]: Precise version may be found in the [latest CI results](https://dev.azure.com/cppstat/GSL/_build?definitionId=1&branchFilter=26).
-[^2]: Precise version may be found in the [latest CI results](https://dev.azure.com/cppstat/GSL/_build?definitionId=1&branchFilter=26). Should be the version specified [here](https://github.com/actions/virtual-environments/blob/main/images/linux/Ubuntu2004-Readme.md#language-and-runtime).
-[^3]: Precise version may be found in the [latest CI results](https://dev.azure.com/cppstat/GSL/_build?definitionId=1&branchFilter=26). Should be the version specified [here](https://github.com/actions/virtual-environments/blob/main/images/win/Windows2022-Readme.md#visual-studio-enterprise-2022).
-[^4]: Precise version may be found in the [latest CI results](https://dev.azure.com/cppstat/GSL/_build?definitionId=1&branchFilter=26). Should be the version specified [here](https://github.com/actions/virtual-environments/blob/main/images/win/Windows2019-Readme.md#visual-studio-enterprise-2019).
+ GCC | 10, 11, 12
+ XCode | 14.3.1, 15.4
+ Clang | 13, 14, 15
+ Visual Studio with MSVC | VS2019, VS2022 
+ Visual Studio with LLVM | VS2019, VS2022
 
 ---
 If you successfully port GSL to another platform, we would love to hear from you!
@@ -216,3 +209,7 @@ target_link_libraries(foobar PRIVATE Microsoft.GSL::GSL)
 ## Debugging visualization support
 
 For Visual Studio users, the file [GSL.natvis](./GSL.natvis) in the root directory of the repository can be added to your project if you would like more helpful visualization of GSL types in the Visual Studio debugger than would be offered by default.
+
+## See Also
+
+For information on [Microsoft Gray Systems Lab (GSL)](https://aka.ms/gsl) of applied data management and system research see <https://aka.ms/gsl>.

azure-pipelines.yml

@@ -1,66 +0,0 @@
-trigger:
-  - main
-
-pr:
-  autoCancel: true
-
-stages:
-- stage: GCC
-  dependsOn: []
-  jobs:
-  - template: ./pipelines/jobs.yml
-    parameters:
-      compiler: gcc
-      image: ubuntu-20.04
-      compilerVersions: [ 11, 10 ]
-      setupfile: 'setup_gcc.yml'
-
-- stage: Clang
-  dependsOn: []
-  jobs:
-  - template: ./pipelines/jobs.yml
-    parameters:
-      compiler: clang
-      image: ubuntu-20.04
-      compilerVersions: [ 12, 11 ]
-      setupfile: 'setup_clang.yml'
-
-- stage: Xcode
-  dependsOn: []
-  jobs:
-  - template: ./pipelines/jobs.yml
-    parameters:
-      compiler: 'Xcode'
-      image: macOS-11
-      compilerVersions: [ '12.5.1', '13.2.1' ]
-      setupfile: 'setup_apple.yml'
-
-- stage: VS_MSVC
-  dependsOn: []
-  jobs:
-  - template: ./pipelines/jobs.yml
-    parameters:
-      compiler: 'VS2019 (MSVC)'
-      compilerVersions: [ 'default' ]
-      image: windows-2019
-  - template: ./pipelines/jobs.yml
-    parameters:
-      compiler: 'VS2022 (MSVC)'
-      compilerVersions: [ 'default' ]
-      image: windows-2022
-
-- stage: VS_LLVM
-  dependsOn: []
-  jobs:
-  - template: ./pipelines/jobs.yml
-    parameters:
-      compiler: 'VS2019 (LLVM)'
-      compilerVersions: [ 'default' ]
-      image: windows-2019
-      extraCmakeArgs: '-T ClangCL'
-  - template: ./pipelines/jobs.yml
-    parameters:
-      compiler: 'VS2022 (LLVM)'
-      compilerVersions: [ 'default' ]
-      image: windows-2022
-      extraCmakeArgs: '-T ClangCL'

include/gsl/narrow

@@ -30,13 +30,12 @@ struct narrowing_error : public std::exception
 template <class T, class U, typename std::enable_if<std::is_arithmetic<T>::value>::type* = nullptr>
 // clang-format off
 GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
-GSL_SUPPRESS(f.6) // NO-FORMAT: attribute // TODO: MSVC /analyze does not recognise noexcept(false)
 GSL_SUPPRESS(es.46) // NO-FORMAT: attribute // The warning suggests that a floating->unsigned conversion can occur
                                             // in the static_cast below, and that gsl::narrow should be used instead.
                                             // Suppress this warning, since gsl::narrow is defined in terms of
                                             // static_cast
     // clang-format on
-    constexpr T narrow(U u) noexcept(false)
+    constexpr T narrow(U u)
 {
     constexpr const bool is_different_signedness =
         (std::is_signed<T>::value != std::is_signed<U>::value);
@@ -67,9 +66,8 @@ GSL_SUPPRESS(p.2) // NO-FORMAT: attribute // don't rely on undefined behavior
 template <class T, class U, typename std::enable_if<!std::is_arithmetic<T>::value>::type* = nullptr>
 // clang-format off
 GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
-GSL_SUPPRESS(f.6) // NO-FORMAT: attribute // TODO: MSVC /analyze does not recognise noexcept(false)
     // clang-format on
-    constexpr T narrow(U u) noexcept(false)
+    constexpr T narrow(U u)
 {
     const T t = narrow_cast<T>(u);
 

include/gsl/pointers

@@ -19,12 +19,11 @@
 
 #include "assert" // for Ensures, Expects
 
-#include <algorithm>    // for forward
 #include <cstddef>      // for ptrdiff_t, nullptr_t, size_t
-#include <memory>       // for shared_ptr, unique_ptr
-#include <system_error> // for hash
+#include <functional>   // for less, greater
+#include <memory>       // for shared_ptr, unique_ptr, hash
 #include <type_traits>  // for enable_if_t, is_convertible, is_assignable
-#include <utility>      // for declval
+#include <utility>      // for declval, forward
 
 #if !defined(GSL_NO_IOSTREAMS)
 #include <iosfwd> // for ostream

pipelines/jobs.yml

@@ -1,43 +0,0 @@
-parameters:
-  CXXVersions: [ 14, 17, 20 ]
-  buildTypes: [ 'Debug', 'Release' ]
-  image: ''
-
-  compiler: ''
-  compilerVersions: ["default"] # if default value, simply uses whatever version is on the machine.
-                                # the text of this default value doesn't actually matter.
-  setupfile: ''
-  extraCmakeArgs: ''
-
-jobs:
-- ${{ each compilerVersion in parameters.compilerVersions }}:
-  - ${{ each CXXVersion in parameters.CXXVersions }}:
-    - ${{ each buildType in parameters.buildTypes }}:
-      - job:
-        displayName: ${{ format('{0} {1} C++{2} {3}', parameters.compiler, compilerVersion, CXXVersion, buildType) }}
-        pool:
-            vmImage: ${{ parameters.image }}
-        continueOnError: false
-
-        steps:
-          - ${{ if not(eq(parameters.setupfile, '')) }}:
-            - template: ${{ parameters.setupfile }}
-              parameters:
-                version: ${{ compilerVersion }}
-
-          - task: CMake@1
-            name: Configure
-            inputs:
-              workingDirectory: build
-              cmakeArgs: '-DGSL_CXX_STANDARD=${{ CXXVersion }} -DCMAKE_BUILD_TYPE=${{ buildType }} -DCI_TESTING:BOOL=ON -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON -Werror=dev ${{ parameters.extraCmakeArgs }} .. '
-
-          - task: CMake@1
-            name: Build
-            inputs:
-              workingDirectory: build
-              cmakeArgs: '--build . '
-
-          - script: ctest . --output-on-failure --no-compress-output
-            name: CTest
-            workingDirectory: build
-            failOnStderr: true

pipelines/setup_apple.yml

@@ -1,9 +0,0 @@
-parameters:
-    version: 0
-
-steps:
-  - script: |
-      if [ "${{ parameters.version }}" != "default" ]; then sudo xcode-select -switch /Applications/Xcode_${{ parameters.version }}.app; fi
-
-    displayName: "Setup Xcode Version"
-    failOnStderr: true

pipelines/setup_clang.yml

@@ -1,13 +0,0 @@
-parameters:
-    version: 0
-
-steps:
-  - script: |
-      echo "##vso[task.setvariable variable=CXX;]${CXX}"
-      echo "##vso[task.setvariable variable=CC;]${CC}"
-
-    displayName: "Setup Clang Version"
-    failOnStderr: true
-    env:
-      CC: clang-${{ parameters.version }}
-      CXX: clang++-${{ parameters.version }}

pipelines/setup_gcc.yml

@@ -1,14 +0,0 @@
-parameters:
-    version: 0
-
-steps:
-  - script: |
-      echo "##vso[task.setvariable variable=CXX;]${CXX}"
-      echo "##vso[task.setvariable variable=CC;]${CC}"
-      if [ "${{ parameters.version }}" = "11" ]; then sudo apt-get install $CXX; fi
-
-    displayName: "Setup GCC Version"
-    failOnStderr: true
-    env:
-      CC: gcc-${{ parameters.version }}
-      CXX: g++-${{ parameters.version }}