[libc] fix aarch64 linux full build

[SchrodingerZhu]

fix #95349

Additionally,

• enable some entrypoints that should be available on aarch64
• fix another missing symbol problem __getauxval

[llvmbot]

@llvm/pr-subscribers-libc

Author: Schrodinger ZHU Yifan (SchrodingerZhu)

Changes

fix #95349

Additionally,

• enable some entrypoints that should be available on aarch64
• fix another missing symbol problem __getauxval

---

Full diff: https://github.com/llvm/llvm-project/pull/95358.diff

3 Files Affected:

• (modified) libc/config/linux/aarch64/entrypoints.txt (+7)
• (modified) libc/src/__support/threads/linux/CMakeLists.txt (+20-5)
• (modified) libc/test/IntegrationTest/test.cpp (+6)

diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
index db96a80051a8d..7ce088689b925 100644
--- a/libc/config/linux/aarch64/entrypoints.txt
+++ b/libc/config/linux/aarch64/entrypoints.txt
@@ -643,6 +643,12 @@ if(LLVM_LIBC_FULL_BUILD)
     libc.src.pthread.pthread_mutexattr_setrobust
     libc.src.pthread.pthread_mutexattr_settype
     libc.src.pthread.pthread_once
+    libc.src.pthread.pthread_rwlockattr_destroy
+    libc.src.pthread.pthread_rwlockattr_getkind_np
+    libc.src.pthread.pthread_rwlockattr_getpshared
+    libc.src.pthread.pthread_rwlockattr_init
+    libc.src.pthread.pthread_rwlockattr_setkind_np
+    libc.src.pthread.pthread_rwlockattr_setpshared
     libc.src.pthread.pthread_setspecific
 
     # sched.h entrypoints
@@ -753,6 +759,7 @@ if(LLVM_LIBC_FULL_BUILD)
     libc.src.unistd._exit
     libc.src.unistd.environ
     libc.src.unistd.execv
+    libc.src.unistd.fork
     libc.src.unistd.getopt
     libc.src.unistd.optarg
     libc.src.unistd.optind
diff --git a/libc/src/__support/threads/linux/CMakeLists.txt b/libc/src/__support/threads/linux/CMakeLists.txt
index 9bf88ccc84557..95e509b7a825d 100644
--- a/libc/src/__support/threads/linux/CMakeLists.txt
+++ b/libc/src/__support/threads/linux/CMakeLists.txt
@@ -22,11 +22,11 @@ add_header_library(
     libc.src.__support.time.linux.abs_timeout
 )
 
-set(raw_mutex_additional_flags)
+set(monotonicity_flags)
 if (LIBC_CONF_TIMEOUT_ENSURE_MONOTONICITY)
-  set(raw_mutex_additional_flags -DLIBC_COPT_TIMEOUT_ENSURE_MONOTONICITY=1)
+  set(monotonicity_flags -DLIBC_COPT_TIMEOUT_ENSURE_MONOTONICITY=1)
 else()
-  set(raw_mutex_additional_flags -DLIBC_COPT_TIMEOUT_ENSURE_MONOTONICITY=0)
+  set(monotonicity_flags -DLIBC_COPT_TIMEOUT_ENSURE_MONOTONICITY=0)
 endif()
 
 add_header_library(
@@ -42,8 +42,22 @@ add_header_library(
     libc.hdr.types.pid_t
   COMPILE_OPTIONS
     -DLIBC_COPT_RAW_MUTEX_DEFAULT_SPIN_COUNT=${LIBC_CONF_RAW_MUTEX_DEFAULT_SPIN_COUNT}
-    ${raw_mutex_additional_flags}
-  
+    ${monotonicity_flags}
+)
+
+add_header_library(
+  rwlock
+  HDRS
+    rwlock.h
+  DEPENDS
+    .futex_utils
+    .raw_mutex
+    libc.src.__support.common
+    libc.src.__support.OSUtil.osutil
+    libc.src.__support.CPP.limits
+  COMPILE_OPTIONS
+    -DLIBC_COPT_RWLOCK_DEFAULT_SPIN_COUNT=${LIBC_CONF_RWLOCK_DEFAULT_SPIN_COUNT}
+    ${monotonicity_flags}
 )
 
 add_header_library(
@@ -64,6 +78,7 @@ add_object_library(
     .futex_utils
     libc.config.linux.app_h
     libc.include.sys_syscall
+    libc.include.fcntl
     libc.src.errno.errno
     libc.src.__support.CPP.atomic
     libc.src.__support.CPP.stringstream
diff --git a/libc/test/IntegrationTest/test.cpp b/libc/test/IntegrationTest/test.cpp
index 3bdbe89a3fb62..27e7f29efa0f1 100644
--- a/libc/test/IntegrationTest/test.cpp
+++ b/libc/test/IntegrationTest/test.cpp
@@ -79,4 +79,10 @@ void *realloc(void *ptr, size_t s) {
 // Integration tests are linked with -nostdlib. BFD linker expects
 // __dso_handle when -nostdlib is used.
 void *__dso_handle = nullptr;
+
+// On some platform (aarch64 fedora tested) full build integration test
+// objects need to link against libgcc, which may expect a __getauxval
+// function. For now, it is fine to provide a weak definition that always
+// returns false.
+[[gnu::weak]] bool __getauxval(uint64_t, uint64_t *) { return false; }
 } // extern "C"

[lntue]

will changing thread.cpp to use hdr/fcntl_macros.h and add libc.hdr.fcntl_macros dependency work?

[SchrodingerZhu]

I suppose thread.cpp is built only in full build mode?

[lntue]

You're right: #93241