Retire GCC FORTIFY.
NDK r18 (which removes GCC) is about to ship. We don't need this any more.
The immediate motivation for removing this right now is that the test
fails whenever we add Clang-only flags to the build system.
While we're here, clean up <stdatomic.h> too.
Bug: https://issuetracker.google.com/74404306
Test: ran tests
Change-Id: Iaad5d634d1ba76f0b6f19ad32cc27b2533771a4a
diff --git a/libc/include/stdatomic.h b/libc/include/stdatomic.h
index 013407e..3c61334 100644
--- a/libc/include/stdatomic.h
+++ b/libc/include/stdatomic.h
@@ -33,11 +33,7 @@
#include <sys/cdefs.h>
#if defined(__cplusplus) && __cplusplus >= 201103L && defined(_USING_LIBCXX)
-# ifdef __clang__
-# if __has_feature(cxx_atomic)
-# define _STDATOMIC_HAVE_ATOMIC
-# endif
-# else /* gcc */
+# if __has_feature(cxx_atomic)
# define _STDATOMIC_HAVE_ATOMIC
# endif
#endif
@@ -150,20 +146,6 @@
# include <uchar.h> /* For char16_t and char32_t. */
#endif
-
-#ifdef __clang__
-# if __has_extension(c_atomic) || __has_extension(cxx_atomic)
-# define __CLANG_ATOMICS
-# else
-# error "stdatomic.h does not support your compiler"
-# endif
-# if __has_builtin(__sync_swap)
-# define __HAS_BUILTIN_SYNC_SWAP
-# endif
-#else
-# define __GNUC_ATOMICS
-#endif
-
/*
* 7.17.1 Atomic lock-free macros.
*/
@@ -203,13 +185,8 @@
* 7.17.2 Initialization.
*/
-#if defined(__CLANG_ATOMICS)
#define ATOMIC_VAR_INIT(value) (value)
#define atomic_init(obj, value) __c11_atomic_init(obj, value)
-#else
-#define ATOMIC_VAR_INIT(value) { .__val = (value) }
-#define atomic_init(obj, value) ((void)((obj)->__val = (value)))
-#endif
/*
* Clang and recent GCC both provide predefined macros for the memory
@@ -258,63 +235,24 @@
* 7.17.4 Fences.
*/
-static __inline void
-atomic_thread_fence(memory_order __order __attribute__((unused)))
-{
-
-#ifdef __CLANG_ATOMICS
+static __inline void atomic_thread_fence(memory_order __order __attribute__((unused))) {
__c11_atomic_thread_fence(__order);
-#elif defined(__GNUC_ATOMICS)
- __atomic_thread_fence(__order);
-#else
- __sync_synchronize();
-#endif
}
-static __inline void
-atomic_signal_fence(memory_order __order __attribute__((unused)))
-{
-
-#ifdef __CLANG_ATOMICS
+static __inline void atomic_signal_fence(memory_order __order __attribute__((unused))) {
__c11_atomic_signal_fence(__order);
-#elif defined(__GNUC_ATOMICS)
- __atomic_signal_fence(__order);
-#else
- __asm volatile ("" ::: "memory");
-#endif
}
/*
* 7.17.5 Lock-free property.
*/
-#if defined(_KERNEL)
-/* Atomics in kernelspace are always lock-free. */
-#define atomic_is_lock_free(obj) \
- ((void)(obj), (_Bool)1)
-#elif defined(__CLANG_ATOMICS)
-#define atomic_is_lock_free(obj) \
- __c11_atomic_is_lock_free(sizeof(*(obj)))
-#elif defined(__GNUC_ATOMICS)
-#define atomic_is_lock_free(obj) \
- __atomic_is_lock_free(sizeof((obj)->__val), &(obj)->__val)
-#else
-#define atomic_is_lock_free(obj) \
- ((void)(obj), sizeof((obj)->__val) <= sizeof(void *))
-#endif
+#define atomic_is_lock_free(obj) __c11_atomic_is_lock_free(sizeof(*(obj)))
/*
* 7.17.6 Atomic integer types.
*/
-#ifndef __CLANG_ATOMICS
-/*
- * No native support for _Atomic(). Place object in structure to prevent
- * most forms of direct non-atomic access.
- */
-#define _Atomic(T) struct { T volatile __val; }
-#endif
-
typedef _Atomic(bool) atomic_bool;
typedef _Atomic(char) atomic_char;
typedef _Atomic(signed char) atomic_schar;
@@ -363,7 +301,6 @@
* Compiler-specific operations.
*/
-#if defined(__CLANG_ATOMICS)
#define atomic_compare_exchange_strong_explicit(object, expected, \
desired, success, failure) \
__c11_atomic_compare_exchange_strong(object, expected, desired, \
@@ -388,91 +325,11 @@
__c11_atomic_load(object, order)
#define atomic_store_explicit(object, desired, order) \
__c11_atomic_store(object, desired, order)
-#elif defined(__GNUC_ATOMICS)
-#define atomic_compare_exchange_strong_explicit(object, expected, \
- desired, success, failure) \
- __atomic_compare_exchange_n(&(object)->__val, expected, \
- desired, 0, success, failure)
-#define atomic_compare_exchange_weak_explicit(object, expected, \
- desired, success, failure) \
- __atomic_compare_exchange_n(&(object)->__val, expected, \
- desired, 1, success, failure)
-#define atomic_exchange_explicit(object, desired, order) \
- __atomic_exchange_n(&(object)->__val, desired, order)
-#define atomic_fetch_add_explicit(object, operand, order) \
- __atomic_fetch_add(&(object)->__val, operand, order)
-#define atomic_fetch_and_explicit(object, operand, order) \
- __atomic_fetch_and(&(object)->__val, operand, order)
-#define atomic_fetch_or_explicit(object, operand, order) \
- __atomic_fetch_or(&(object)->__val, operand, order)
-#define atomic_fetch_sub_explicit(object, operand, order) \
- __atomic_fetch_sub(&(object)->__val, operand, order)
-#define atomic_fetch_xor_explicit(object, operand, order) \
- __atomic_fetch_xor(&(object)->__val, operand, order)
-#define atomic_load_explicit(object, order) \
- __atomic_load_n(&(object)->__val, order)
-#define atomic_store_explicit(object, desired, order) \
- __atomic_store_n(&(object)->__val, desired, order)
-#else
-#define __atomic_apply_stride(object, operand) \
- (((__typeof__((object)->__val))0) + (operand))
-#define atomic_compare_exchange_strong_explicit(object, expected, \
- desired, success, failure) __extension__ ({ \
- __typeof__(expected) __ep = (expected); \
- __typeof__(*__ep) __e = *__ep; \
- (void)(success); (void)(failure); \
- (bool)((*__ep = __sync_val_compare_and_swap(&(object)->__val, \
- __e, desired)) == __e); \
-})
-#define atomic_compare_exchange_weak_explicit(object, expected, \
- desired, success, failure) \
- atomic_compare_exchange_strong_explicit(object, expected, \
- desired, success, failure)
-#ifdef __HAS_BUILTIN_SYNC_SWAP
-/* Clang provides a full-barrier atomic exchange - use it if available. */
-#define atomic_exchange_explicit(object, desired, order) \
- ((void)(order), __sync_swap(&(object)->__val, desired))
-#else
-/*
- * __sync_lock_test_and_set() is only an acquire barrier in theory (although in
- * practice it is usually a full barrier) so we need an explicit barrier before
- * it.
- */
-#define atomic_exchange_explicit(object, desired, order) \
-__extension__ ({ \
- __typeof__(object) __o = (object); \
- __typeof__(desired) __d = (desired); \
- (void)(order); \
- __sync_synchronize(); \
- __sync_lock_test_and_set(&(__o)->__val, __d); \
-})
-#endif
-#define atomic_fetch_add_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_add(&(object)->__val, \
- __atomic_apply_stride(object, operand)))
-#define atomic_fetch_and_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_and(&(object)->__val, operand))
-#define atomic_fetch_or_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_or(&(object)->__val, operand))
-#define atomic_fetch_sub_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_sub(&(object)->__val, \
- __atomic_apply_stride(object, operand)))
-#define atomic_fetch_xor_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_xor(&(object)->__val, operand))
-#define atomic_load_explicit(object, order) \
- ((void)(order), __sync_fetch_and_add(&(object)->__val, 0))
-#define atomic_store_explicit(object, desired, order) \
- ((void)atomic_exchange_explicit(object, desired, order))
-#endif
/*
* Convenience functions.
- *
- * Don't provide these in kernel space. In kernel space, we should be
- * disciplined enough to always provide explicit barriers.
*/
-#ifndef _KERNEL
#define atomic_compare_exchange_strong(object, expected, desired) \
atomic_compare_exchange_strong_explicit(object, expected, \
desired, memory_order_seq_cst, memory_order_seq_cst)
@@ -495,7 +352,6 @@
atomic_load_explicit(object, memory_order_seq_cst)
#define atomic_store(object, desired) \
atomic_store_explicit(object, desired, memory_order_seq_cst)
-#endif /* !_KERNEL */
/*
* 7.17.8 Atomic flag type and operations.
@@ -510,36 +366,21 @@
#define ATOMIC_FLAG_INIT { ATOMIC_VAR_INIT(false) }
-static __inline bool
-atomic_flag_test_and_set_explicit(volatile atomic_flag *__object,
- memory_order __order)
-{
+static __inline bool atomic_flag_test_and_set_explicit(volatile atomic_flag *__object, memory_order __order) {
return (atomic_exchange_explicit(&__object->__flag, 1, __order));
}
-static __inline void
-atomic_flag_clear_explicit(volatile atomic_flag *__object, memory_order __order)
-{
-
+static __inline void atomic_flag_clear_explicit(volatile atomic_flag *__object, memory_order __order) {
atomic_store_explicit(&__object->__flag, 0, __order);
}
-#ifndef _KERNEL
-static __inline bool
-atomic_flag_test_and_set(volatile atomic_flag *__object)
-{
-
- return (atomic_flag_test_and_set_explicit(__object,
- memory_order_seq_cst));
+static __inline bool atomic_flag_test_and_set(volatile atomic_flag *__object) {
+ return (atomic_flag_test_and_set_explicit(__object, memory_order_seq_cst));
}
-static __inline void
-atomic_flag_clear(volatile atomic_flag *__object)
-{
-
+static __inline void atomic_flag_clear(volatile atomic_flag *__object) {
atomic_flag_clear_explicit(__object, memory_order_seq_cst);
}
-#endif /* !_KERNEL */
#endif /* <atomic> unavailable */