[libc++] Remove official Clang 18 support. #130142
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Since Clang 20 has been release we no longer support Clang 18 per our policy. Note the Clang 18 workarounds will be removed in a follow-up patch.
llvmbot
added
libc++
|
@llvm/pr-subscribers-github-workflow Author: Mark de Wever (mordante) ChangesSince Clang 20 has been release we no longer support Clang 18 per our policy. Note the Clang 18 workarounds will be removed in a follow-up patch. Full diff: https://github.com/llvm/llvm-project/pull/130142.diff 3 Files Affected:
diff --git a/.github/workflows/libcxx-build-and-test.yaml b/.github/workflows/libcxx-build-and-test.yaml
index 5d4394435890a..74889adfa070f 100644
--- a/.github/workflows/libcxx-build-and-test.yaml
+++ b/.github/workflows/libcxx-build-and-test.yaml
@@ -100,10 +100,6 @@ jobs:
- config: 'generic-cxx26'
cc: 'clang-19'
cxx: 'clang++-19'
- # Release transition
- - config: 'generic-cxx23'
- cc: 'clang-18'
- cxx: 'clang++-18'
steps:
- uses: actions/checkout@v4
- name: ${{ matrix.config }}
diff --git a/libcxx/docs/index.rst b/libcxx/docs/index.rst
index e2c62e9ecac02..a8b0d5ce1ee97 100644
--- a/libcxx/docs/index.rst
+++ b/libcxx/docs/index.rst
@@ -131,7 +131,7 @@ velocity, libc++ drops support for older compilers as newer ones are released.
============ =================== ========================== =====================
Compiler Versions Restrictions Support policy
============ =================== ========================== =====================
-Clang 18, 19, 20, 21-git latest two stable releases per `LLVM's release page <https://releases.llvm.org>`_ and the development version
+Clang 19, 20, 21-git latest two stable releases per `LLVM's release page <https://releases.llvm.org>`_ and the development version
AppleClang 15 latest stable release per `Xcode's release page <https://developer.apple.com/documentation/xcode-release-notes>`_
Open XL 17.1.3 (AIX) latest stable release per `Open XL's documentation page <https://www.ibm.com/docs/en/openxl-c-and-cpp-aix>`_
GCC 14 In C++11 or later only latest stable release per `GCC's release page <https://gcc.gnu.org/releases.html>`_
diff --git a/libcxx/include/__configuration/compiler.h b/libcxx/include/__configuration/compiler.h
index cf459a0619b23..4b6c6cad353e3 100644
--- a/libcxx/include/__configuration/compiler.h
+++ b/libcxx/include/__configuration/compiler.h
@@ -33,8 +33,8 @@
// Warn if a compiler version is used that is not supported anymore
// LLVM RELEASE Update the minimum compiler versions
# if defined(_LIBCPP_CLANG_VER)
-# if _LIBCPP_CLANG_VER < 1800
-# warning "Libc++ only supports Clang 18 and later"
+# if _LIBCPP_CLANG_VER < 1900
+# warning "Libc++ only supports Clang 19 and later"
# endif
# elif defined(_LIBCPP_APPLE_CLANG_VER)
# if _LIBCPP_APPLE_CLANG_VER < 1500
|
|
@llvm/pr-subscribers-libcxx Author: Mark de Wever (mordante) ChangesSince Clang 20 has been release we no longer support Clang 18 per our policy. Note the Clang 18 workarounds will be removed in a follow-up patch. Full diff: https://github.com/llvm/llvm-project/pull/130142.diff 3 Files Affected:
diff --git a/.github/workflows/libcxx-build-and-test.yaml b/.github/workflows/libcxx-build-and-test.yaml
index 5d4394435890a..74889adfa070f 100644
--- a/.github/workflows/libcxx-build-and-test.yaml
+++ b/.github/workflows/libcxx-build-and-test.yaml
@@ -100,10 +100,6 @@ jobs:
- config: 'generic-cxx26'
cc: 'clang-19'
cxx: 'clang++-19'
- # Release transition
- - config: 'generic-cxx23'
- cc: 'clang-18'
- cxx: 'clang++-18'
steps:
- uses: actions/checkout@v4
- name: ${{ matrix.config }}
diff --git a/libcxx/docs/index.rst b/libcxx/docs/index.rst
index e2c62e9ecac02..a8b0d5ce1ee97 100644
--- a/libcxx/docs/index.rst
+++ b/libcxx/docs/index.rst
@@ -131,7 +131,7 @@ velocity, libc++ drops support for older compilers as newer ones are released.
============ =================== ========================== =====================
Compiler Versions Restrictions Support policy
============ =================== ========================== =====================
-Clang 18, 19, 20, 21-git latest two stable releases per `LLVM's release page <https://releases.llvm.org>`_ and the development version
+Clang 19, 20, 21-git latest two stable releases per `LLVM's release page <https://releases.llvm.org>`_ and the development version
AppleClang 15 latest stable release per `Xcode's release page <https://developer.apple.com/documentation/xcode-release-notes>`_
Open XL 17.1.3 (AIX) latest stable release per `Open XL's documentation page <https://www.ibm.com/docs/en/openxl-c-and-cpp-aix>`_
GCC 14 In C++11 or later only latest stable release per `GCC's release page <https://gcc.gnu.org/releases.html>`_
diff --git a/libcxx/include/__configuration/compiler.h b/libcxx/include/__configuration/compiler.h
index cf459a0619b23..4b6c6cad353e3 100644
--- a/libcxx/include/__configuration/compiler.h
+++ b/libcxx/include/__configuration/compiler.h
@@ -33,8 +33,8 @@
// Warn if a compiler version is used that is not supported anymore
// LLVM RELEASE Update the minimum compiler versions
# if defined(_LIBCPP_CLANG_VER)
-# if _LIBCPP_CLANG_VER < 1800
-# warning "Libc++ only supports Clang 18 and later"
+# if _LIBCPP_CLANG_VER < 1900
+# warning "Libc++ only supports Clang 19 and later"
# endif
# elif defined(_LIBCPP_APPLE_CLANG_VER)
# if _LIBCPP_APPLE_CLANG_VER < 1500
|
philnik777
approved these changes
Mar 6, 2025
|
Linaro is working on updating to 19. |
ldionne
approved these changes
Mar 18, 2025
|
Sorry for the delay, our workers are using 19.1.7 now and should pass the next build you do. As of 2 weeks ago there were no problems with the test suite on Arm with this clang, but I am available to debug anything you might find now. |
DavidSpickett
approved these changes
Mar 25, 2025
Thanks a lot for updating the bots! |
DavidSpickett
added a commit
to DavidSpickett/llvm-project
that referenced
this pull request
Mar 27, 2025
clang-19 changed how Arm triples were normalised and so while we supported 18 and 19, we could not hard code the path here. Now that Linaro's bots are running clang-19, and libcxx is going to drop clang-18 support (llvm#130142) I have simplified it by hard coding the path again. I also looked into why this exists in the first place. It was added in https://reviews.llvm.org/D154246 but not questioned at the time. It is due to the way we build compiler-rt, which is due to the final layout we need in the install: 1. The builtins library must be called libclang_rt.builtins.a for clang to find it. There must not be an architecture name in the filename. 2. That builtins library must be directly in lib/, next to picolib's installed files. To achieve #1 we must set LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON. However, that causes the file to be installed in a per-target dir which breaks #2. So to fix that, we move the builtins library up one level into lib/. The alternative is to turn off per-target dirs, which results in a builtin file with an arch in the name, then rename and move that file (since it gets installed into lib/generic/). So in the end, it's the same amount of hacks. I think it's best to keep the one that uses LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON, as this is the recommended way to built these days.
DavidSpickett
added a commit
that referenced
this pull request
Mar 28, 2025
clang-19 changed how Arm triples were normalised and so while we supported 18 and 19, we could not hard code the path here. Now that Linaro's bots are running clang-19, and libcxx is going to drop clang-18 support (#130142) I have simplified it by hard coding the path again. I also looked into why this exists in the first place. It was added in https://reviews.llvm.org/D154246 but not questioned at the time. It is due to the way we build compiler-rt, which is due to the final layout we need in the install: 1. The builtins library must be called libclang_rt.builtins.a for clang to find it. There must not be an architecture name in the filename. 2. That builtins library must be directly in lib/, next to picolib's installed files. To achieve number 1 we must set LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON. However, that causes the file to be installed in a per-target dir which breaks number 2. So to fix that, we move the builtins library up one level into lib/. The alternative is to turn off per-target dirs, which results in a builtin file with an arch in the name, then rename and move that file (since it gets installed into lib/generic/). So in the end, it's the same amount of hacks. I think it's best to keep the one that uses LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON, as this is the recommended way to built these days.
llvm-sync bot
pushed a commit
to arm/arm-toolchain
that referenced
this pull request
Mar 28, 2025
…254) clang-19 changed how Arm triples were normalised and so while we supported 18 and 19, we could not hard code the path here. Now that Linaro's bots are running clang-19, and libcxx is going to drop clang-18 support (llvm/llvm-project#130142) I have simplified it by hard coding the path again. I also looked into why this exists in the first place. It was added in https://reviews.llvm.org/D154246 but not questioned at the time. It is due to the way we build compiler-rt, which is due to the final layout we need in the install: 1. The builtins library must be called libclang_rt.builtins.a for clang to find it. There must not be an architecture name in the filename. 2. That builtins library must be directly in lib/, next to picolib's installed files. To achieve number 1 we must set LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON. However, that causes the file to be installed in a per-target dir which breaks number 2. So to fix that, we move the builtins library up one level into lib/. The alternative is to turn off per-target dirs, which results in a builtin file with an arch in the name, then rename and move that file (since it gets installed into lib/generic/). So in the end, it's the same amount of hacks. I think it's best to keep the one that uses LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON, as this is the recommended way to built these days.
This was referenced Apr 1, 2025
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Since Clang 20 has been release we no longer support Clang 18 per our policy.
Note the Clang 18 workarounds will be removed in a follow-up patch.