[libc] Move libc_errno.h to libc/src/__support and make LIBC_ERRNO_MODE_SYSTEM to be header-only. #143187
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@llvm/pr-subscribers-libc Author: None (lntue) ChangesThis is the first step in preparation for: https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450 Patch is 308.08 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/143187.diff 407 Files Affected:
diff --git a/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake b/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake
index 0facb0b9be0c1..a98e7276bef80 100644
--- a/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake
+++ b/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake
@@ -106,6 +106,10 @@ function(_get_compile_options_from_config output_var)
list(APPEND config_options "-DLIBC_MATH=${LIBC_CONF_MATH_OPTIMIZATIONS}")
endif()
+ if(LIBC_CONF_ERRNO_MODE)
+ set(APPEND config_options "-DLIBC_ERRNO_MODE=${LIBC_CONF_ERRNO_MODE}")
+ endif()
+
set(${output_var} ${config_options} PARENT_SCOPE)
endfunction(_get_compile_options_from_config)
diff --git a/libc/docs/dev/code_style.rst b/libc/docs/dev/code_style.rst
index 0bd3a69ae3ffe..86247966552f9 100644
--- a/libc/docs/dev/code_style.rst
+++ b/libc/docs/dev/code_style.rst
@@ -101,7 +101,7 @@ test infrastructure itself can be affected. To avoid perturbing the unit test
infrastructure around the setting of ``errno``, the following rules are to be
followed:
-#. A special macro named ``libc_errno`` defined in ``src/errno/libc_errno.h``
+#. A special macro named ``libc_errno`` defined in ``src/__support/libc_errno.h``
should be used when setting ``errno`` from libc runtime code. For example,
code to set ``errno`` to ``EINVAL`` should be:
@@ -117,7 +117,7 @@ followed:
`ErrorOr <https://github.com/llvm/llvm-project/blob/main/libc/src/__support/error_or.h>`_
to return error values.
-#. The header file ``src/errno/libc_errno.h`` is shipped as part of the target
+#. The header file ``src/__support/libc_errno.h`` is shipped as part of the target
corresponding to the ``errno`` entrypoint ``libc.src.errno.errno``. We do
not in general allow dependencies between entrypoints. However, the ``errno``
entrypoint is the only exceptional entrypoint on which other entrypoints
diff --git a/libc/shared/fp_bits.h b/libc/shared/fp_bits.h
index 2898c508b7772..e6bb1e17b80c9 100644
--- a/libc/shared/fp_bits.h
+++ b/libc/shared/fp_bits.h
@@ -9,6 +9,7 @@
#ifndef LLVM_LIBC_SHARED_FP_BITS_H
#define LLVM_LIBC_SHARED_FP_BITS_H
+#include "libc_common.h"
#include "src/__support/FPUtil/FPBits.h"
namespace LIBC_NAMESPACE_DECL {
diff --git a/libc/shared/libc_common.h b/libc/shared/libc_common.h
new file mode 100644
index 0000000000000..837eb3c1f692e
--- /dev/null
+++ b/libc/shared/libc_common.h
@@ -0,0 +1,20 @@
+//===-- Common defines for sharing LLVM libc with LLVM projects -*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SHARED_LIBC_COMMON_H
+#define LLVM_LIBC_SHARED_LIBC_COMMON_H
+
+// Use system errno.
+#undef LIBC_ERRNO_MODE
+#define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_SYSTEM
+
+#ifndef LIBC_NAMESPACE
+#define LIBC_NAMESPACE __llvm_libc
+#endif // LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SHARED_LIBC_COMMON_H
diff --git a/libc/shared/rpc_server.h b/libc/shared/rpc_server.h
index 5509094b944ad..46e35f13f0eac 100644
--- a/libc/shared/rpc_server.h
+++ b/libc/shared/rpc_server.h
@@ -9,6 +9,7 @@
#ifndef LLVM_LIBC_SHARED_RPC_SERVER_H
#define LLVM_LIBC_SHARED_RPC_SERVER_H
+#include "libc_common.h"
#include "src/__support/RPC/rpc_server.h"
namespace LIBC_NAMESPACE_DECL {
diff --git a/libc/shared/str_to_float.h b/libc/shared/str_to_float.h
index b133a28e26efc..dcc6027d6c77f 100644
--- a/libc/shared/str_to_float.h
+++ b/libc/shared/str_to_float.h
@@ -9,6 +9,7 @@
#ifndef LLVM_LIBC_SHARED_STR_TO_FLOAT_H
#define LLVM_LIBC_SHARED_STR_TO_FLOAT_H
+#include "libc_common.h"
#include "src/__support/str_to_float.h"
namespace LIBC_NAMESPACE_DECL {
diff --git a/libc/shared/str_to_integer.h b/libc/shared/str_to_integer.h
index 15bee698d5a6b..6ed38c932662e 100644
--- a/libc/shared/str_to_integer.h
+++ b/libc/shared/str_to_integer.h
@@ -9,6 +9,7 @@
#ifndef LLVM_LIBC_SHARED_STR_TO_INTEGER_H
#define LLVM_LIBC_SHARED_STR_TO_INTEGER_H
+#include "libc_common.h"
#include "src/__support/str_to_integer.h"
namespace LIBC_NAMESPACE_DECL {
diff --git a/libc/src/__support/CMakeLists.txt b/libc/src/__support/CMakeLists.txt
index f92499fdbf451..327ff5e0c6a37 100644
--- a/libc/src/__support/CMakeLists.txt
+++ b/libc/src/__support/CMakeLists.txt
@@ -1,6 +1,15 @@
add_subdirectory(CPP)
add_subdirectory(macros)
+add_header_library(
+ libc_errno
+ HDRS
+ libc_errno.h
+ DEPENDS
+ libc.hdr.errno_macros
+ libc.src.__support.macros.config
+)
+
add_header_library(
block
HDRS
diff --git a/libc/src/__support/FPUtil/FEnvImpl.h b/libc/src/__support/FPUtil/FEnvImpl.h
index 4c8f34a435bdf..50a101f833c55 100644
--- a/libc/src/__support/FPUtil/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/FEnvImpl.h
@@ -12,10 +12,10 @@
#include "hdr/fenv_macros.h"
#include "hdr/math_macros.h"
#include "hdr/types/fenv_t.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/attributes.h" // LIBC_INLINE
#include "src/__support/macros/config.h"
#include "src/__support/macros/properties/architectures.h"
-#include "src/errno/libc_errno.h"
#if defined(LIBC_TARGET_ARCH_IS_AARCH64) && defined(__ARM_FP)
#if defined(__APPLE__)
diff --git a/libc/src/__support/File/dir.cpp b/libc/src/__support/File/dir.cpp
index 21b0106f70106..aea8862c15f7f 100644
--- a/libc/src/__support/File/dir.cpp
+++ b/libc/src/__support/File/dir.cpp
@@ -11,8 +11,8 @@
#include "src/__support/CPP/mutex.h" // lock_guard
#include "src/__support/CPP/new.h"
#include "src/__support/error_or.h"
+#include "src/__support/libc_errno.h" // For error macros
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h" // For error macros
namespace LIBC_NAMESPACE_DECL {
diff --git a/libc/src/__support/File/file.cpp b/libc/src/__support/File/file.cpp
index 528542cccf324..303852dbbb717 100644
--- a/libc/src/__support/File/file.cpp
+++ b/libc/src/__support/File/file.cpp
@@ -13,8 +13,8 @@
#include "hdr/types/off_t.h"
#include "src/__support/CPP/new.h"
#include "src/__support/CPP/span.h"
+#include "src/__support/libc_errno.h" // For error macros
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h" // For error macros
namespace LIBC_NAMESPACE_DECL {
diff --git a/libc/src/__support/File/linux/file.cpp b/libc/src/__support/File/linux/file.cpp
index 824c1f200e8c5..761e352f74ead 100644
--- a/libc/src/__support/File/linux/file.cpp
+++ b/libc/src/__support/File/linux/file.cpp
@@ -15,8 +15,8 @@
#include "src/__support/File/linux/lseekImpl.h"
#include "src/__support/OSUtil/fcntl.h"
#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
+#include "src/__support/libc_errno.h" // For error macros
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h" // For error macros
#include "hdr/fcntl_macros.h" // For mode_t and other flags to the open syscall
#include <sys/stat.h> // For S_IS*, S_IF*, and S_IR* flags.
diff --git a/libc/src/__support/File/linux/lseekImpl.h b/libc/src/__support/File/linux/lseekImpl.h
index a034913d9f6ec..300e5c5dd55bf 100644
--- a/libc/src/__support/File/linux/lseekImpl.h
+++ b/libc/src/__support/File/linux/lseekImpl.h
@@ -13,8 +13,8 @@
#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
#include "src/__support/common.h"
#include "src/__support/error_or.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h"
#include <stdint.h> // For uint64_t.
#include <sys/syscall.h> // For syscall numbers.
diff --git a/libc/src/__support/HashTable/randomness.h b/libc/src/__support/HashTable/randomness.h
index 244dd41be3eec..6b58a4125f785 100644
--- a/libc/src/__support/HashTable/randomness.h
+++ b/libc/src/__support/HashTable/randomness.h
@@ -14,7 +14,7 @@
#include "src/__support/macros/attributes.h"
#include "src/__support/macros/config.h"
#if defined(LIBC_HASHTABLE_USE_GETRANDOM)
-#include "src/errno/libc_errno.h"
+#include "src/__support/libc_errno.h"
#include "src/sys/random/getrandom.h"
#endif
diff --git a/libc/src/__support/OSUtil/linux/fcntl.cpp b/libc/src/__support/OSUtil/linux/fcntl.cpp
index 4742b2a00220b..99e16ad58c918 100644
--- a/libc/src/__support/OSUtil/linux/fcntl.cpp
+++ b/libc/src/__support/OSUtil/linux/fcntl.cpp
@@ -15,8 +15,8 @@
#include "hdr/types/struct_flock64.h"
#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h"
#include <stdarg.h>
#include <sys/syscall.h> // For syscall numbers.
diff --git a/libc/src/__support/OSUtil/linux/vdso.cpp b/libc/src/__support/OSUtil/linux/vdso.cpp
index 8c9bd3e1bcc72..e4e53c3c2a0f2 100644
--- a/libc/src/__support/OSUtil/linux/vdso.cpp
+++ b/libc/src/__support/OSUtil/linux/vdso.cpp
@@ -11,9 +11,9 @@
#include "src/__support/CPP/array.h"
#include "src/__support/CPP/optional.h"
#include "src/__support/CPP/string_view.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/threads/callonce.h"
#include "src/__support/threads/linux/futex_word.h"
-#include "src/errno/libc_errno.h"
#include "src/sys/auxv/getauxval.h"
#include <linux/auxvec.h>
diff --git a/libc/src/__support/StringUtil/tables/linux_extension_errors.h b/libc/src/__support/StringUtil/tables/linux_extension_errors.h
index 425590f6e91c9..de637d60bea97 100644
--- a/libc/src/__support/StringUtil/tables/linux_extension_errors.h
+++ b/libc/src/__support/StringUtil/tables/linux_extension_errors.h
@@ -10,8 +10,8 @@
#define LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_TABLES_LINUX_EXTENSION_ERRORS_H
#include "src/__support/StringUtil/message_mapper.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h"
namespace LIBC_NAMESPACE_DECL {
diff --git a/libc/src/__support/libc_errno.h b/libc/src/__support/libc_errno.h
new file mode 100644
index 0000000000000..a48622d754b8a
--- /dev/null
+++ b/libc/src/__support/libc_errno.h
@@ -0,0 +1,96 @@
+//===-- Implementation header for libc_errno --------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_LIBC_ERRNO_H
+#define LLVM_LIBC_SRC___SUPPORT_LIBC_ERRNO_H
+
+// This header is to be consumed by internal implementations, in which all of
+// them should refer to `libc_errno` instead of using `errno` directly from
+// <errno.h> header.
+
+// Unit and hermetic tests should:
+// - #include "src/__support/libc_errno.h"
+// - NOT #include <errno.h>
+// - Only use `libc_errno` in the code
+// - Depend on libc.src.errno.errno
+
+// Integration tests should:
+// - NOT #include "src/__support/libc_errno.h"
+// - #include <errno.h>
+// - Use regular `errno` in the code
+// - Still depend on libc.src.errno.errno
+
+// libc uses a fallback default value, either system or thread local.
+#define LIBC_ERRNO_MODE_DEFAULT 0
+// libc never stores a value; `errno` macro uses get link-time failure.
+#define LIBC_ERRNO_MODE_UNDEFINED 1
+// libc maintains per-thread state (requires C++ `thread_local` support).
+#define LIBC_ERRNO_MODE_THREAD_LOCAL 2
+// libc maintains shared state used by all threads, contrary to standard C
+// semantics unless always single-threaded; nothing prevents data races.
+#define LIBC_ERRNO_MODE_SHARED 3
+// libc doesn't maintain any internal state, instead the embedder must define
+// `int *__llvm_libc_errno(void);` C function.
+#define LIBC_ERRNO_MODE_EXTERNAL 4
+// libc uses system `<errno.h>` `errno` macro directly in the overlay mode; in
+// fullbuild mode, effectively the same as `LIBC_ERRNO_MODE_EXTERNAL`.
+#define LIBC_ERRNO_MODE_SYSTEM 5
+
+#if !defined(LIBC_ERRNO_MODE) || LIBC_ERRNO_MODE == LIBC_ERRNO_MODE_DEFAULT
+#undef LIBC_ERRNO_MODE
+#if defined(LIBC_FULL_BUILD) || !defined(LIBC_COPT_PUBLIC_PACKAGING)
+#define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_THREAD_LOCAL
+#else
+#define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_SYSTEM
+#endif
+#endif // LIBC_ERRNO_MODE
+
+#if LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_DEFAULT && \
+ LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_UNDEFINED && \
+ LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_THREAD_LOCAL && \
+ LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_SHARED && \
+ LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_EXTERNAL && \
+ LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_SYSTEM
+#error LIBC_ERRNO_MODE must be one of the following values: \
+LIBC_ERRNO_MODE_DEFAULT, \
+LIBC_ERRNO_MODE_UNDEFINED, \
+LIBC_ERRNO_MODE_THREAD_LOCAL, \
+LIBC_ERRNO_MODE_SHARED, \
+LIBC_ERRNO_MODE_EXTERNAL, \
+LIBC_ERRNO_MODE_SYSTEM
+#endif
+
+#if LIBC_ERRNO_MODE == LIBC_ERRNO_MODE_SYSTEM
+
+#include <errno.h>
+
+#define libc_errno errno
+
+#else // !LIBC_ERRNO_MODE_SYSTEM
+
+#include "hdr/errno_macros.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+extern "C" int *__llvm_libc_errno() noexcept;
+
+struct Errno {
+ void operator=(int);
+ operator int();
+};
+
+extern Errno libc_errno;
+
+} // namespace LIBC_NAMESPACE_DECL
+
+using LIBC_NAMESPACE::libc_errno;
+
+#endif // LIBC_ERRNO_MODE_SYSTEM
+
+#endif // LLVM_LIBC_SRC___SUPPORT_LIBC_ERRNO_H
diff --git a/libc/src/__support/threads/linux/thread.cpp b/libc/src/__support/threads/linux/thread.cpp
index c531d74c53355..baad26aed6851 100644
--- a/libc/src/__support/threads/linux/thread.cpp
+++ b/libc/src/__support/threads/linux/thread.cpp
@@ -14,9 +14,9 @@
#include "src/__support/OSUtil/syscall.h" // For syscall functions.
#include "src/__support/common.h"
#include "src/__support/error_or.h"
+#include "src/__support/libc_errno.h" // For error macros
#include "src/__support/macros/config.h"
#include "src/__support/threads/linux/futex_utils.h" // For FutexWordType
-#include "src/errno/libc_errno.h" // For error macros
#ifdef LIBC_TARGET_ARCH_IS_AARCH64
#include <arm_acle.h>
diff --git a/libc/src/dirent/closedir.cpp b/libc/src/dirent/closedir.cpp
index 1249ef94cf411..2f8f6f0c044db 100644
--- a/libc/src/dirent/closedir.cpp
+++ b/libc/src/dirent/closedir.cpp
@@ -10,8 +10,8 @@
#include "src/__support/File/dir.h"
#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h"
#include <dirent.h>
diff --git a/libc/src/dirent/opendir.cpp b/libc/src/dirent/opendir.cpp
index fee14ef0f558d..bf47d0edac180 100644
--- a/libc/src/dirent/opendir.cpp
+++ b/libc/src/dirent/opendir.cpp
@@ -10,8 +10,8 @@
#include "src/__support/File/dir.h"
#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h"
#include <dirent.h>
diff --git a/libc/src/dirent/readdir.cpp b/libc/src/dirent/readdir.cpp
index ad460b5e80b8b..f95f7c1ae8646 100644
--- a/libc/src/dirent/readdir.cpp
+++ b/libc/src/dirent/readdir.cpp
@@ -10,8 +10,8 @@
#include "src/__support/File/dir.h"
#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/config.h"
-#include "src/errno/libc_errno.h"
#include <dirent.h>
diff --git a/libc/src/errno/CMakeLists.txt b/libc/src/errno/CMakeLists.txt
index 1d78a5eedff96..2852044e94164 100644
--- a/libc/src/errno/CMakeLists.txt
+++ b/libc/src/errno/CMakeLists.txt
@@ -1,28 +1,16 @@
# If we are in full build mode, we will provide the errno definition ourselves,
# and if we are in overlay mode, we will just re-use the system's errno.
-# We are passing LIBC_FULL_BUILD flag in full build mode so that the
-# implementation of libc_errno will know if we are in full build mode or not.
-
-# TODO: Move LIBC_FULL_BUILD flag to _get_common_compile_options.
-set(full_build_flag "")
-if(LLVM_LIBC_FULL_BUILD)
- set(full_build_flag "-DLIBC_FULL_BUILD")
-endif()
-
-if(LIBC_CONF_ERRNO_MODE)
- set(errno_config_copts "-DLIBC_ERRNO_MODE=${LIBC_CONF_ERRNO_MODE}")
-endif()
add_entrypoint_object(
errno
SRCS
libc_errno.cpp
HDRS
- libc_errno.h # Include this
- COMPILE_OPTIONS
- ${full_build_flag}
- ${errno_config_copts}
+ ../__support/libc_errno.h
DEPENDS
libc.hdr.errno_macros
libc.src.__support.common
+ libc.src.__support.libc_errno
+ libc.src.__support.macros.attributes
+ libc.src.__support.macros.config
)
diff --git a/libc/src/errno/libc_errno.cpp b/libc/src/errno/libc_errno.cpp
index d1600d1b050e3..5d319031faf36 100644
--- a/libc/src/errno/libc_errno.cpp
+++ b/libc/src/errno/libc_errno.cpp
@@ -6,51 +6,14 @@
//
//===----------------------------------------------------------------------===//
-#include "libc_errno.h"
+#include "src/__support/libc_errno.h"
+#include "src/__support/macros/attributes.h"
#include "src/__support/macros/config.h"
-// libc uses a fallback default value, either system or thread local.
-#define LIBC_ERRNO_MODE_DEFAULT 0
-// libc never stores a value; `errno` macro uses get link-time failure.
-#define LIBC_ERRNO_MODE_UNDEFINED 1
-// libc maintains per-thread state (requires C++ `thread_local` support).
-#define LIBC_ERRNO_MODE_THREAD_LOCAL 2
-// libc maintains shared state used by all threads, contrary to standard C
-// semantics unless always single-threaded; nothing prevents data races.
-#define LIBC_ERRNO_MODE_SHARED 3
-// libc doesn't maintain any internal state, instead the embedder must define
-// `int *__llvm_libc_errno(void);` C function.
-#define LIBC_ERRNO_MODE_EXTERNAL 4
-// libc uses system `<errno.h>` `errno` macro directly in the overlay mode; in
-// fullbuild mode, effectively the same as `LIBC_ERRNO_MODE_EXTERNAL`.
-#define LIBC_ERRNO_MODE_SYSTEM 5
-
-#if !defined(LIBC_ERRNO_MODE) || LIBC_ERRNO_MODE == LIBC_ERRNO_MODE_DEFAULT
-#undef LIBC_ERRNO_MODE
-#if defined(LIBC_FULL_BUILD) || !defined(LIBC_COPT_PUBLIC_PACKAGING)
-#define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_THREAD_LOCAL
-#else
-#define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_SYSTEM
-#endif
-#endif // LIBC_ERRNO_MODE
-
-#if LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_DEFAULT && \
- LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_UNDEFINED && \
- LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_THREAD_LOCAL && \
- LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_SHARED && \
- LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_EXTERNAL && \
- LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_SYSTEM
-#error LIBC_ERRNO_MODE must be one of the following values: \
-LIBC_ERRNO_MODE_DEFAULT, \
-LIBC_ERRNO_MODE_UNDEFINED, \
-LIBC_ERRNO_MODE_THREAD_LOCAL, \
-LIBC_ERRNO_MODE_SHARED, \
-LIBC_ERRNO_MODE_EXTERNAL, \
-LIBC_ERRNO_MODE_SYSTEM
-#endif
-
namespace LIBC_NAMESPACE_DECL {
+#if LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_SYSTEM
+
#if LIBC_ERRNO_MODE == LIBC_ERRNO_MODE_UNDEFINED
void Errno::operator=(int) {}
@@ -83,14 +46,11 @@ Errno::operator int() { return shared_errno; }
void Errno::operator=(int a) { *__llvm_libc_errno() = a; }
Errno::operator int() { return *__llvm_libc_errno(); }
-#elif LIBC_ERRNO_MODE == LIBC_ERRNO_MODE_SYSTEM
-
-void Errno::operator=(int a) { errno = a; }
-Errno::operator int() { return errno; }
-
#endif
// Define the global `libc_errno` instance.
Errno libc_errno;
+#endif // LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_SYSTEM
+
} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/errno/libc_errno.h b/libc/src/errno/libc_errno.h
deleted file mode 100644
index 44ee2714843ba..0000000000000
--- a/libc/src/errno/libc_errno.h
+++ /dev/null
@@ -1,47 +0,0 @@
-//===-- Implementation header for libc_errno --------------------*- C++ -*-===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIBC_SRC_ERRNO_LIBC...
[truncated]
|
vonosmas
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libc/shared/libc_common.h
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|
|
||
| // Use system errno. | ||
| #undef LIBC_ERRNO_MODE | ||
| #define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_SYSTEM |
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I think it would already be the default behavior? Looks like LIBC_ERRNO_MODE defaults to LIBC_ERRNO_MODE_SYSTEM when it's not a production build?
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By default, without setting LIBC_COPT_PUBLIC_PACKAGING, LIBC_ERRNO_MODE will be set to LIBC_ERRNO_MODE_THREAD_LOCAL.
Previously, everywhere in our code base, it is pointed to LIBC_NAMESPACE::libc_errno symbol, which will be resolved by either libc.src.errno.errno target or libc.src.errno.errno.__internal__ target. This is for being shared with libc++ and other LLVM projects, which will (and should) only use the system errno at the moment.
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Ah, thanks for correction - I see now that by default including libc/shared from a non-llvm-libc code would pick LIBC_ERRNO_MODE_THREAD_LOCAL, and that's not what we want. I'm OK with somehow forcing LIBC_ERRNO_MODE_SYSTEM somehow, but wonder how to do it reliably. I.e. if you forget to include libc/shared/libc_common.h inside a different libc/shared/ header, you may end up transitively including libc/__support/libc_errno.h, and defining LIBC_ERRNO_MODE to something else...
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I guess we can enforce that with clang-tidy check and bot?
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Is there a use case when LIBC_ERRNO_MODE may be explicitly set to something else but LIBC_ERRNO_MODE_SYSTEM_INLINE when using llvm-libc code though libc/shared? If no, then how about we:
- Teach llvm-libc headers to "understand" when they are being used in "shared" mode (i.e. by
#define LIBC_SHARED_MODEinlibc/shared/libc_common.hheader, or by omitting this header file entirely, and using this define in everylibc/shared/file which currently is modified to includelibc/shared/libc_common.h) - In
src/__support/libc_errno.h: make it an error to explicitly#define LIBC_ERRNO_MODEto anything butLIBC_ERRNO_MODE_SYSTEM_INLINE.
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It will be easier to enforce that in libc/shared/libc_common.h, basically just error out if LIBC_ERRNO_MODE is defined and not set as LIBC_ERRNO_MODE_SYSTEM_INLINE. Once it is set as such, src/__support/libc_errno.h will not change it.
That's simpler than putting the enforcement in src/__support/libc_errno.h, because it needs some signal / macro definition from libc/shared folder anyway.
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Sure, I think this check would also work (provided we add clang-tidy check you refer to to enforce the libc_common.h is included where needed.
|
Have you considered changing |
There's a TODO in the code and #143454 filed to address this. |
…DE_SYSTEM to be header-only.
…and LIBC_NAMESPACE::libc_errno -> libc_errno.
…IBC_ERRNO_MODE_SYSTEM_INLINE in shared/libc_common.h
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Since errno was moved in llvm#143187 the code including it in llvm#141393 was rendered incorrect. This patch fixes the include and the cmake depends.
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Since errno was moved in llvm/llvm-project#143187 the code including it in llvm/llvm-project#141393 was rendered incorrect. This patch fixes the include and the cmake depends.
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Docgen updates the docs when the config options are changed. This update has been waiting since llvm#143187.
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Docgen updates the docs when the config options are changed. This update has been waiting since #143187.
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Docgen updates the docs when the config options are changed. This update has been waiting since llvm/llvm-project#143187.
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…DE_SYSTEM to be header-only. (llvm#143187) This is the first step in preparation for: https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450
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Since errno was moved in llvm#143187 the code including it in llvm#141393 was rendered incorrect. This patch fixes the include and the cmake depends.
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Docgen updates the docs when the config options are changed. This update has been waiting since llvm#143187.
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…DE_SYSTEM to be header-only. (llvm#143187) This is the first step in preparation for: https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450
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Since errno was moved in llvm#143187 the code including it in llvm#141393 was rendered incorrect. This patch fixes the include and the cmake depends.
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Docgen updates the docs when the config options are changed. This update has been waiting since llvm#143187.
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This is the first step in preparation for: https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450