[libc-commits] [libc] [libc] Add LLVM_LIBC_ENABLE_EXPERIMENTAL_ENTRYPOINTS CMake flag (PR #197537)

Wed May 13 23:04:39 PDT 2026

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `libc-x86_64-debian-fullbuild-dbg` running on `libc-x86_64-debian-fullbuild` while building `libc` at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/179/builds/46952

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 4 (annotate) failure: 'python ../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py ...' (failure)
...
-- Doxygen disabled.
-- Setting LIBC_NAMESPACE namespace to '__llvm_libc_20_0_0_git'
-- Set COMPILER_RESOURCE_DIR to /usr/lib/llvm-14/lib/clang/14.0.6 using --print-resource-dir
-- Building libc for x86_64 on linux with LIBC_COMPILE_OPTIONS_DEFAULT: 
-- LIBC_COPT_USE_C_ASSERT: OFF
-- LIBC_CONF_ENABLE_STRONG_STACK_PROTECTOR: ON
-- LIBC_CONF_KEEP_FRAME_POINTER: ON
-- LIBC_CONF_CTYPE_SMALLER_ASCII: OFF
-- LIBC_CONF_ERRNO_MODE: LIBC_ERRNO_MODE_DEFAULT
-- LIBC_CONF_TRAP_ON_RAISE_FP_EXCEPT: OFF
-- LIBC_ADD_NULL_CHECKS: ON
-- LIBC_CONF_FREXP_INF_NAN_EXPONENT: 
-- LIBC_CONF_MATH_OPTIMIZATIONS: 0
-- LIBC_CONF_MATH_USE_SYSTEM_FENV: OFF
-- LIBC_CONF_PRINTF_DISABLE_FIXED_POINT: OFF
-- LIBC_CONF_PRINTF_DISABLE_FLOAT: OFF
-- LIBC_CONF_PRINTF_DISABLE_INDEX_MODE: OFF
-- LIBC_CONF_PRINTF_DISABLE_STRERROR: OFF
-- LIBC_CONF_PRINTF_DISABLE_WIDE: OFF
-- LIBC_CONF_PRINTF_DISABLE_WRITE_INT: OFF
-- LIBC_CONF_PRINTF_FLOAT_TO_STR_NO_SPECIALIZE_LD: OFF
-- LIBC_CONF_PRINTF_FLOAT_TO_STR_USE_DYADIC_FLOAT: OFF
-- LIBC_CONF_PRINTF_FLOAT_TO_STR_USE_FLOAT320: OFF
-- LIBC_CONF_PRINTF_FLOAT_TO_STR_USE_MEGA_LONG_DOUBLE_TABLE: OFF
-- LIBC_CONF_PRINTF_MODULAR: OFF
-- LIBC_CONF_PRINTF_RUNTIME_DISPATCH: ON
-- LIBC_COPT_PRINTF_DISABLE_BITINT: OFF
-- LIBC_CONF_RAW_MUTEX_DEFAULT_SPIN_COUNT: 100
-- LIBC_CONF_RWLOCK_DEFAULT_SPIN_COUNT: 100
-- LIBC_CONF_TIMEOUT_ENSURE_MONOTONICITY: ON
-- LIBC_CONF_QSORT_IMPL: LIBC_QSORT_QUICK_SORT
-- LIBC_CONF_SCANF_DISABLE_FLOAT: OFF
-- LIBC_CONF_SCANF_DISABLE_INDEX_MODE: OFF
-- LIBC_CONF_SETJMP_AARCH64_RESTORE_PLATFORM_REGISTER: ON
-- LIBC_CONF_STRTOFLOAT_DISABLE_CLINGER_FAST_PATH: OFF
-- LIBC_CONF_STRTOFLOAT_DISABLE_EISEL_LEMIRE: OFF
-- LIBC_CONF_STRTOFLOAT_DISABLE_SIMPLE_DECIMAL_CONVERSION: OFF
-- LIBC_CONF_COPT_MEMCPY_X86_USE_NTA_STORES: OFF
-- LIBC_CONF_FIND_FIRST_CHARACTER_IMPL: element
-- LIBC_CONF_MEMSET_X86_USE_SOFTWARE_PREFETCHING: OFF
-- LIBC_CONF_STRING_LENGTH_IMPL: element
-- LIBC_CONF_THREAD_MODE: LIBC_THREAD_MODE_PLATFORM
-- LIBC_CONF_TIME_64BIT: OFF
-- LIBC_CONF_WCTYPE_MODE: LIBC_WCTYPE_MODE_ASCII
-- Writing config doc to /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/libc/docs/configure.rst
-- Overriding - LIBC_CONF_FIND_FIRST_CHARACTER_IMPL: word (Previous value: element)
-- Overriding - LIBC_CONF_STRING_LENGTH_IMPL: clang_vector (Previous value: element)
-- Set CPU features: AVX;AVX2;FMA;SSE2;SSE4_2
-- Compiler features available: builtin_fmax_fmin;builtin_isnan;cfloat128;float128
-- Using getrandom for hashtable randomness
Step 5 (cmake) failure: cmake (failure)
...
CMake Error at /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:151 (add_library):
  Error evaluating generator expression:

    $<TARGET_OBJECTS:libc.src.unistd.sysconf>

  Objects of target "libc.src.unistd.sysconf" referenced but is not one of
  the allowed target types (EXECUTABLE, STATIC, SHARED, MODULE, OBJECT).
Call Stack (most recent call first):
  /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/test/integration/scudo/CMakeLists.txt:13 (add_entrypoint_library)
CMake Error at /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:151 (add_library):
  Error evaluating generator expression:

    $<TARGET_OBJECTS:libc.src.unistd.sysconf>

  Objects of target "libc.src.unistd.sysconf" referenced but is not one of
  the allowed target types (EXECUTABLE, STATIC, SHARED, MODULE, OBJECT).
Call Stack (most recent call first):
  /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/test/integration/scudo/CMakeLists.txt:13 (add_entrypoint_library)

CMake Error at /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:151 (add_library):
  Error evaluating generator expression:

    $<TARGET_OBJECTS:libc.src.unistd.sysconf>

  Objects of target "libc.src.unistd.sysconf" referenced but is not one of
  the allowed target types (EXECUTABLE, STATIC, SHARED, MODULE, OBJECT).
Call Stack (most recent call first):
  /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/test/integration/scudo/CMakeLists.txt:13 (add_entrypoint_library)
CMake Error at /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/cmake/modules/LLVMLibCLibraryRules.cmake:151 (add_library):
  No SOURCES given to target: libc_for_scudo_integration_test
Call Stack (most recent call first):
  /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-project/libc/test/integration/scudo/CMakeLists.txt:13 (add_entrypoint_library)

CMake Generate step failed.  Build files cannot be regenerated correctly.
['cmake', '../llvm-project/runtimes', '-GNinja', '-DCMAKE_C_COMPILER=clang', '-DCMAKE_CXX_COMPILER=clang++', '-DCMAKE_BUILD_TYPE=Debug', '-DLLVM_ENABLE_RUNTIMES=libc;compiler-rt', '-DLLVM_LIBC_INCLUDE_SCUDO=ON', '-DCOMPILER_RT_BUILD_SCUDO_STANDALONE_WITH_LLVM_LIBC=ON', '-DCOMPILER_RT_BUILD_GWP_ASAN=OFF', '-DCOMPILER_RT_SCUDO_STANDALONE_BUILD_SHARED=OFF', '-DLLVM_LIBC_FULL_BUILD=ON'] exited with return code 1.
The build step threw an exception...
Traceback (most recent call last):
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py", line 181, in step
    yield
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py", line 135, in main
    run_command(['cmake', os.path.join(source_dir, cmake_root)] + cmake_args)
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/build/../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py", line 196, in run_command
    util.report_run_cmd(cmd, cwd=directory)
  File "/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian-fullbuild/libc-x86_64-debian-fullbuild-dbg/llvm-zorg/zorg/buildbot/builders/annotated/util.py", line 49, in report_run_cmd
    subprocess.check_call(cmd, shell=shell, *args, **kwargs)
  File "/usr/lib/python3.11/subprocess.py", line 413, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['cmake', '../llvm-project/runtimes', '-GNinja', '-DCMAKE_C_COMPILER=clang', '-DCMAKE_CXX_COMPILER=clang++', '-DCMAKE_BUILD_TYPE=Debug', '-DLLVM_ENABLE_RUNTIMES=libc;compiler-rt', '-DLLVM_LIBC_INCLUDE_SCUDO=ON', '-DCOMPILER_RT_BUILD_SCUDO_STANDALONE_WITH_LLVM_LIBC=ON', '-DCOMPILER_RT_BUILD_GWP_ASAN=OFF', '-DCOMPILER_RT_SCUDO_STANDALONE_BUILD_SHARED=OFF', '-DLLVM_LIBC_FULL_BUILD=ON']' returned non-zero exit status 1.

```

</details>

https://github.com/llvm/llvm-project/pull/197537