[libcxx] [libcxxabi] [libunwind] [llvm] [libcxxabi][libunwind] Support for using LLVM libc (PR #134893)
Petr Hosek via cfe-commits
cfe-commits at lists.llvm.org
Tue Apr 8 10:42:05 PDT 2025
https://github.com/petrhosek created https://github.com/llvm/llvm-project/pull/134893
This generalizes the support added in #99287 renaming the option to RUNTIMES_USE_LIBC and integrating the module into libc++abi and libunwind as well.
>From 1677ee5c547018472a1f6a29282d3af3500abcd7 Mon Sep 17 00:00:00 2001
From: Petr Hosek <phosek at google.com>
Date: Fri, 2 Aug 2024 08:25:53 -0700
Subject: [PATCH] [libcxxabi][libunwind] Support for using LLVM libc
This generalizes the support added in #99287 renaming the option to
RUNTIMES_USE_LIBC and integrating the module into libc++abi and
libunwind as well.
---
libcxx/CMakeLists.txt | 8 -----
libcxx/cmake/Modules/HandleLibC.cmake | 39 --------------------
libcxx/include/CMakeLists.txt | 2 +-
libcxx/src/CMakeLists.txt | 4 +--
libcxxabi/CMakeLists.txt | 2 ++
libcxxabi/cmake/Modules/HandleLibC.cmake | 39 ++++++++++++++++++++
libcxxabi/src/CMakeLists.txt | 14 ++++----
libunwind/CMakeLists.txt | 2 ++
libunwind/cmake/Modules/HandleLibC.cmake | 39 ++++++++++++++++++++
libunwind/src/CMakeLists.txt | 14 ++++----
runtimes/cmake/Modules/HandleLibC.cmake | 46 ++++++++++++++++++++++++
11 files changed, 147 insertions(+), 62 deletions(-)
delete mode 100644 libcxx/cmake/Modules/HandleLibC.cmake
create mode 100644 libcxxabi/cmake/Modules/HandleLibC.cmake
create mode 100644 libunwind/cmake/Modules/HandleLibC.cmake
create mode 100644 runtimes/cmake/Modules/HandleLibC.cmake
diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index ebaa6e9fd0e97..d3003cbec3889 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -225,14 +225,6 @@ set(LIBCXX_ABI_DEFINES "" CACHE STRING "A semicolon separated list of ABI macros
set(LIBCXX_EXTRA_SITE_DEFINES "" CACHE STRING "Extra defines to add into __config_site")
option(LIBCXX_USE_COMPILER_RT "Use compiler-rt instead of libgcc" OFF)
-# C Library options -----------------------------------------------------------
-
-set(LIBCXX_SUPPORTED_C_LIBRARIES system llvm-libc)
-set(LIBCXX_LIBC "system" CACHE STRING "Specify C library to use. Supported values are ${LIBCXX_SUPPORTED_C_LIBRARIES}.")
-if (NOT "${LIBCXX_LIBC}" IN_LIST LIBCXX_SUPPORTED_C_LIBRARIES)
- message(FATAL_ERROR "Unsupported C library: '${LIBCXX_CXX_ABI}'. Supported values are ${LIBCXX_SUPPORTED_C_LIBRARIES}.")
-endif()
-
# ABI Library options ---------------------------------------------------------
if (MSVC)
set(LIBCXX_DEFAULT_ABI_LIBRARY "vcruntime")
diff --git a/libcxx/cmake/Modules/HandleLibC.cmake b/libcxx/cmake/Modules/HandleLibC.cmake
deleted file mode 100644
index 1b0564ae6fcc6..0000000000000
--- a/libcxx/cmake/Modules/HandleLibC.cmake
+++ /dev/null
@@ -1,39 +0,0 @@
-#===============================================================================
-# Define targets for linking against the selected C library
-#
-# After including this file, the following targets are defined:
-# - libcxx-libc-headers: An interface target that allows getting access to the
-# headers of the selected C library.
-# - libcxx-libc-shared: A target representing the selected shared C library.
-# - libcxx-libc-static: A target representing the selected static C library.
-#===============================================================================
-
-# Link against a system-provided libc
-if (LIBCXX_LIBC STREQUAL "system")
- add_library(libcxx-libc-headers INTERFACE)
-
- add_library(libcxx-libc-static INTERFACE)
- add_library(libcxx-libc-shared INTERFACE)
-
-# Link against the in-tree LLVM libc
-elseif (LIBCXX_LIBC STREQUAL "llvm-libc")
- add_library(libcxx-libc-headers INTERFACE)
- target_link_libraries(libcxx-libc-headers INTERFACE libc-headers)
- if(CXX_SUPPORTS_NOSTDLIBINC_FLAG)
- target_compile_options(libcxx-libc-headers INTERFACE "-nostdlibinc")
- endif()
-
- add_library(libcxx-libc-static INTERFACE)
- if (TARGET libc)
- target_link_libraries(libcxx-libc-static INTERFACE libc)
- endif()
- if (TARGET libm)
- target_link_libraries(libcxx-libc-static INTERFACE libm)
- endif()
- if (CXX_SUPPORTS_NOLIBC_FLAG)
- target_link_options(libcxx-libc-static INTERFACE "-nolibc")
- endif()
-
- # TODO: There's no support for building LLVM libc as a shared library yet.
- add_library(libcxx-libc-shared INTERFACE)
-endif()
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index a021b9bb44d67..9058a72ea75ab 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -2121,7 +2121,7 @@ list(APPEND _all_includes "${LIBCXX_GENERATED_INCLUDE_DIR}/libcxx.imp")
add_custom_target(generate-cxx-headers ALL DEPENDS ${_all_includes})
add_library(cxx-headers INTERFACE)
-target_link_libraries(cxx-headers INTERFACE libcxx-libc-headers libcxx-abi-headers)
+target_link_libraries(cxx-headers INTERFACE runtimes-libc-headers libcxx-abi-headers)
add_dependencies(cxx-headers generate-cxx-headers)
# It's important that the arch directory be included first so that its header files
# which interpose on the default include dir be included instead of the default ones.
diff --git a/libcxx/src/CMakeLists.txt b/libcxx/src/CMakeLists.txt
index 4e9bf900af4c5..97fe57a5f24f8 100644
--- a/libcxx/src/CMakeLists.txt
+++ b/libcxx/src/CMakeLists.txt
@@ -175,7 +175,7 @@ include(FindLibcCommonUtils)
# Build the shared library.
add_library(cxx_shared SHARED ${LIBCXX_SOURCES} ${LIBCXX_HEADERS})
target_include_directories(cxx_shared PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
-target_link_libraries(cxx_shared PUBLIC cxx-headers libcxx-libc-shared
+target_link_libraries(cxx_shared PUBLIC cxx-headers runtimes-libc-shared
PRIVATE ${LIBCXX_LIBRARIES}
PRIVATE llvm-libc-common-utilities)
set_target_properties(cxx_shared
@@ -266,7 +266,7 @@ set(CMAKE_STATIC_LIBRARY_PREFIX "lib")
# Build the static library.
add_library(cxx_static STATIC ${LIBCXX_SOURCES} ${LIBCXX_HEADERS})
target_include_directories(cxx_static PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
-target_link_libraries(cxx_static PUBLIC cxx-headers libcxx-libc-static
+target_link_libraries(cxx_static PUBLIC cxx-headers runtimes-libc-static
PRIVATE ${LIBCXX_LIBRARIES}
PRIVATE libcxx-abi-static
PRIVATE llvm-libc-common-utilities)
diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
index 6dcfc51e55321..1b1f25012f605 100644
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -248,6 +248,8 @@ add_library_flags("${LIBCXXABI_ADDITIONAL_LIBRARIES}")
# Configure compiler. Must happen after setting the target flags.
include(config-ix)
+include(HandleLibC) # Setup the C library flags
+
if (CXX_SUPPORTS_NOSTDINCXX_FLAG)
list(APPEND LIBCXXABI_COMPILE_FLAGS -nostdinc++)
# cmake 3.14 and above remove system include paths that are explicitly
diff --git a/libcxxabi/cmake/Modules/HandleLibC.cmake b/libcxxabi/cmake/Modules/HandleLibC.cmake
new file mode 100644
index 0000000000000..0dbf5125d0f9e
--- /dev/null
+++ b/libcxxabi/cmake/Modules/HandleLibC.cmake
@@ -0,0 +1,39 @@
+#===============================================================================
+# Define targets for linking against the selected C library
+#
+# After including this file, the following targets are defined:
+# - libcxxabi-libc-headers: An interface target that allows getting access to the
+# headers of the selected C library.
+# - libcxxabi-libc-shared: A target representing the selected shared C library.
+# - libcxxabi-libc-static: A target representing the selected static C library.
+#===============================================================================
+
+# Link against a system-provided libc
+if (LIBCXXABI_LIBC STREQUAL "system")
+ add_library(libcxxabi-libc-headers INTERFACE)
+
+ add_library(libcxxabi-libc-static INTERFACE)
+ add_library(libcxxabi-libc-shared INTERFACE)
+
+# Link against the in-tree LLVM libc
+elseif (LIBCXXABI_LIBC STREQUAL "llvm-libc")
+ add_library(libcxxabi-libc-headers INTERFACE)
+ target_link_libraries(libcxxabi-libc-headers INTERFACE libc-headers)
+ if(CXX_SUPPORTS_NOSTDLIBINC_FLAG)
+ target_compile_options(libcxxabi-libc-headers INTERFACE "-nostdlibinc")
+ endif()
+
+ add_library(libcxxabi-libc-static INTERFACE)
+ if (TARGET libc)
+ target_link_libraries(libcxxabi-libc-static INTERFACE libc)
+ endif()
+ if (TARGET libm)
+ target_link_libraries(libcxxabi-libc-static INTERFACE libm)
+ endif()
+ if (CXX_SUPPORTS_NOLIBC_FLAG)
+ target_link_options(libcxxabi-libc-static INTERFACE "-nolibc")
+ endif()
+
+ # TODO: There's no support for building LLVM libc as a shared library yet.
+ add_library(libcxxabi-libc-shared INTERFACE)
+endif()
diff --git a/libcxxabi/src/CMakeLists.txt b/libcxxabi/src/CMakeLists.txt
index 0a6fc892a4f69..0675577aed6a1 100644
--- a/libcxxabi/src/CMakeLists.txt
+++ b/libcxxabi/src/CMakeLists.txt
@@ -172,11 +172,12 @@ if (LIBCXXABI_USE_LLVM_UNWINDER)
target_link_libraries(cxxabi_shared_objects PUBLIC unwind_shared)
endif()
endif()
-target_link_libraries(cxxabi_shared_objects PRIVATE cxx-headers ${LIBCXXABI_LIBRARIES})
+target_link_libraries(cxxabi_shared_objects
+ PUBLIC cxxabi-headers
+ PRIVATE cxx-headers runtimes-libc-headers ${LIBCXXABI_LIBRARIES})
if (NOT CXX_SUPPORTS_NOSTDLIBXX_FLAG)
target_link_libraries(cxxabi_shared_objects PRIVATE ${LIBCXXABI_BUILTINS_LIBRARY})
endif()
-target_link_libraries(cxxabi_shared_objects PUBLIC cxxabi-headers)
set_target_properties(cxxabi_shared_objects
PROPERTIES
CXX_EXTENSIONS OFF
@@ -215,7 +216,7 @@ if (ZOS)
endif ()
target_link_libraries(cxxabi_shared
- PUBLIC cxxabi_shared_objects
+ PUBLIC cxxabi_shared_objects runtimes-libc-shared
PRIVATE ${LIBCXXABI_LIBRARIES})
if (LIBCXXABI_ENABLE_SHARED)
@@ -274,8 +275,9 @@ if (LIBCXXABI_USE_LLVM_UNWINDER AND LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC
target_link_libraries(cxxabi_static_objects PUBLIC unwind_static_objects) # propagate usage requirements
target_sources(cxxabi_static_objects PUBLIC $<TARGET_OBJECTS:unwind_static_objects>)
endif()
-target_link_libraries(cxxabi_static_objects PRIVATE cxx-headers ${LIBCXXABI_STATIC_LIBRARIES} ${LIBCXXABI_LIBRARIES})
-target_link_libraries(cxxabi_static_objects PUBLIC cxxabi-headers)
+target_link_libraries(cxxabi_static_objects
+ PUBLIC cxxabi-headers
+ PRIVATE cxx-headers runtimes-libc-headers ${LIBCXXABI_STATIC_LIBRARIES} ${LIBCXXABI_LIBRARIES})
set_target_properties(cxxabi_static_objects
PROPERTIES
CXX_EXTENSIONS OFF
@@ -311,7 +313,7 @@ endif()
add_library(cxxabi_static STATIC)
if (LIBCXXABI_USE_LLVM_UNWINDER AND NOT LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY)
- target_link_libraries(cxxabi_static PUBLIC unwind_static)
+ target_link_libraries(cxxabi_static PUBLIC unwind_static runtimes-libc-static)
endif()
set_target_properties(cxxabi_static
PROPERTIES
diff --git a/libunwind/CMakeLists.txt b/libunwind/CMakeLists.txt
index 3c8499fd33464..cf31ca2d8f52c 100644
--- a/libunwind/CMakeLists.txt
+++ b/libunwind/CMakeLists.txt
@@ -181,6 +181,8 @@ include(HandleLibunwindFlags)
# Configure compiler.
include(config-ix)
+include(HandleLibC) # Setup the C library flags
+
if (LIBUNWIND_USE_COMPILER_RT AND NOT LIBUNWIND_HAS_NODEFAULTLIBS_FLAG)
list(APPEND LIBUNWIND_LINK_FLAGS "-rtlib=compiler-rt")
endif()
diff --git a/libunwind/cmake/Modules/HandleLibC.cmake b/libunwind/cmake/Modules/HandleLibC.cmake
new file mode 100644
index 0000000000000..62f8db17d1e7f
--- /dev/null
+++ b/libunwind/cmake/Modules/HandleLibC.cmake
@@ -0,0 +1,39 @@
+#===============================================================================
+# Define targets for linking against the selected C library
+#
+# After including this file, the following targets are defined:
+# - libunwind-libc-headers: An interface target that allows getting access to the
+# headers of the selected C library.
+# - libunwind-libc-shared: A target representing the selected shared C library.
+# - libunwind-libc-static: A target representing the selected static C library.
+#===============================================================================
+
+# Link against a system-provided libc
+if (LIBUNWIND_LIBC STREQUAL "system")
+ add_library(libunwind-libc-headers INTERFACE)
+
+ add_library(libunwind-libc-static INTERFACE)
+ add_library(libunwind-libc-shared INTERFACE)
+
+# Link against the in-tree LLVM libc
+elseif (LIBUNWIND_LIBC STREQUAL "llvm-libc")
+ add_library(libunwind-libc-headers INTERFACE)
+ target_link_libraries(libunwind-libc-headers INTERFACE libc-headers)
+ if(CXX_SUPPORTS_NOSTDLIBINC_FLAG)
+ target_compile_options(libunwind-libc-headers INTERFACE "-nostdlibinc")
+ endif()
+
+ add_library(libunwind-libc-static INTERFACE)
+ if (TARGET libc)
+ target_link_libraries(libunwind-libc-static INTERFACE libc)
+ endif()
+ if (TARGET libm)
+ target_link_libraries(libunwind-libc-static INTERFACE libm)
+ endif()
+ if (CXX_SUPPORTS_NOLIBC_FLAG)
+ target_link_options(libunwind-libc-static INTERFACE "-nolibc")
+ endif()
+
+ # TODO: There's no support for building LLVM libc as a shared library yet.
+ add_library(libunwind-libc-shared INTERFACE)
+endif()
diff --git a/libunwind/src/CMakeLists.txt b/libunwind/src/CMakeLists.txt
index d69013e5dace1..2c0cd7aa9e2d6 100644
--- a/libunwind/src/CMakeLists.txt
+++ b/libunwind/src/CMakeLists.txt
@@ -160,9 +160,10 @@ if(CMAKE_C_COMPILER_ID STREQUAL MSVC)
else()
target_compile_options(unwind_shared_objects PRIVATE -fno-rtti)
endif()
-target_link_libraries(unwind_shared_objects PRIVATE unwind-headers ${LIBUNWIND_LIBRARIES})
target_compile_options(unwind_shared_objects PUBLIC "${LIBUNWIND_ADDITIONAL_COMPILE_FLAGS}")
-target_link_libraries(unwind_shared_objects PUBLIC "${LIBUNWIND_ADDITIONAL_LIBRARIES}")
+target_link_libraries(unwind_shared_objects
+ PUBLIC "${LIBUNWIND_ADDITIONAL_LIBRARIES}"
+ PRIVATE unwind-headers runtimes-libc-headers ${LIBUNWIND_LIBRARIES})
set_target_properties(unwind_shared_objects
PROPERTIES
CXX_EXTENSIONS OFF
@@ -175,7 +176,7 @@ if (CMAKE_POSITION_INDEPENDENT_CODE OR NOT DEFINED CMAKE_POSITION_INDEPENDENT_CO
endif()
add_library(unwind_shared SHARED)
-target_link_libraries(unwind_shared PUBLIC unwind_shared_objects)
+target_link_libraries(unwind_shared PUBLIC unwind_shared_objects runtimes-libc-shared)
set_target_properties(unwind_shared
PROPERTIES
EXCLUDE_FROM_ALL "$<IF:$<BOOL:${LIBUNWIND_ENABLE_SHARED}>,FALSE,TRUE>"
@@ -201,9 +202,10 @@ if(CMAKE_C_COMPILER_ID STREQUAL MSVC)
else()
target_compile_options(unwind_static_objects PRIVATE -fno-rtti)
endif()
-target_link_libraries(unwind_static_objects PRIVATE unwind-headers ${LIBUNWIND_LIBRARIES})
target_compile_options(unwind_static_objects PUBLIC "${LIBUNWIND_ADDITIONAL_COMPILE_FLAGS}")
-target_link_libraries(unwind_static_objects PUBLIC "${LIBUNWIND_ADDITIONAL_LIBRARIES}")
+target_link_libraries(unwind_static_objects
+ PUBLIC "${LIBUNWIND_ADDITIONAL_LIBRARIES}"
+ PRIVATE unwind-headers runtimes-libc-headers ${LIBUNWIND_LIBRARIES})
set_target_properties(unwind_static_objects
PROPERTIES
CXX_EXTENSIONS OFF
@@ -222,7 +224,7 @@ if(LIBUNWIND_HIDE_SYMBOLS)
endif()
add_library(unwind_static STATIC)
-target_link_libraries(unwind_static PUBLIC unwind_static_objects)
+target_link_libraries(unwind_static PUBLIC unwind_static_objects runtimes-libc-static)
set_target_properties(unwind_static
PROPERTIES
EXCLUDE_FROM_ALL "$<IF:$<BOOL:${LIBUNWIND_ENABLE_STATIC}>,FALSE,TRUE>"
diff --git a/runtimes/cmake/Modules/HandleLibC.cmake b/runtimes/cmake/Modules/HandleLibC.cmake
new file mode 100644
index 0000000000000..8307ef4708725
--- /dev/null
+++ b/runtimes/cmake/Modules/HandleLibC.cmake
@@ -0,0 +1,46 @@
+#===============================================================================
+# Define targets for linking against the selected C library
+#
+# After including this file, the following targets are defined:
+# - runtimes-libc-headers: An interface target that allows getting access to the
+# headers of the selected C library.
+# - runtimes-libc-shared: A target representing the selected shared C library.
+# - runtimes-libc-static: A target representing the selected static C library.
+#===============================================================================
+
+set(RUNTIMES_SUPPORTED_C_LIBRARIES system llvm-libc)
+set(RUNTIMES_USE_LIBC "system" CACHE STRING "Specify C library to use. Supported values are ${RUNTIMES_SUPPORTED_C_LIBRARIES}.")
+if (NOT "${RUNTIMES_USE_LIBC}" IN_LIST RUNTIMES_SUPPORTED_C_LIBRARIES)
+ message(FATAL_ERROR "Unsupported C library: '${RUNTIMES_CXX_ABI}'. Supported values are ${RUNTIMES_SUPPORTED_C_LIBRARIES}.")
+endif()
+
+# Link against a system-provided libc
+if (RUNTIMES_USE_LIBC STREQUAL "system")
+ add_library(runtimes-libc-headers INTERFACE)
+
+ add_library(runtimes-libc-static INTERFACE)
+ add_library(runtimes-libc-shared INTERFACE)
+
+# Link against the in-tree LLVM libc
+elseif (RUNTIMES_USE_LIBC STREQUAL "llvm-libc")
+ add_library(runtimes-libc-headers INTERFACE)
+ target_link_libraries(runtimes-libc-headers INTERFACE libc-headers)
+ check_cxx_compiler_flag(-nostdlibinc CXX_SUPPORTS_NOSTDLIBINC_FLAG)
+ if(CXX_SUPPORTS_NOSTDLIBINC_FLAG)
+ target_compile_options(runtimes-libc-headers INTERFACE "-nostdlibinc")
+ endif()
+
+ add_library(runtimes-libc-static INTERFACE)
+ if (TARGET libc)
+ target_link_libraries(runtimes-libc-static INTERFACE libc)
+ endif()
+ if (TARGET libm)
+ target_link_libraries(runtimes-libc-static INTERFACE libm)
+ endif()
+ if (CXX_SUPPORTS_NOLIBC_FLAG)
+ target_link_options(runtimes-libc-static INTERFACE "-nolibc")
+ endif()
+
+ # TODO: There's no support for building LLVM libc as a shared library yet.
+ add_library(runtimes-libc-shared INTERFACE)
+endif()
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