diff options
| -rw-r--r-- | libc/bionic/system_properties.cpp | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/libc/bionic/system_properties.cpp b/libc/bionic/system_properties.cpp index 30081a59d..ad69cf5f9 100644 --- a/libc/bionic/system_properties.cpp +++ b/libc/bionic/system_properties.cpp @@ -611,6 +611,14 @@ const prop_info *__system_property_find(const char *name) return find_property(root_node(), name, strlen(name), NULL, 0, false); } +// The C11 standard doesn't allow atomic loads from const fields, +// though C++11 does. Fudge it until standards get straightened out. +static inline uint_least32_t load_const_atomic(const atomic_uint_least32_t* s, + memory_order mo) { + atomic_uint_least32_t* non_const_s = const_cast<atomic_uint_least32_t*>(s); + return atomic_load_explicit(non_const_s, mo); +} + int __system_property_read(const prop_info *pi, char *name, char *value) { if (__predict_false(compat_mode)) { @@ -631,7 +639,7 @@ int __system_property_read(const prop_info *pi, char *name, char *value) // would be any different, so this should be OK. atomic_thread_fence(memory_order_acquire); if (serial == - atomic_load_explicit(&(pi->serial), memory_order_relaxed)) { + load_const_atomic(&(pi->serial), memory_order_relaxed)) { if (name != 0) { strcpy(name, pi->name); } @@ -733,12 +741,12 @@ int __system_property_add(const char *name, unsigned int namelen, // Wait for non-locked serial, and retrieve it with acquire semantics. unsigned int __system_property_serial(const prop_info *pi) { - uint32_t serial = atomic_load_explicit(&pi->serial, memory_order_acquire); + uint32_t serial = load_const_atomic(&pi->serial, memory_order_acquire); while (SERIAL_DIRTY(serial)) { __futex_wait(const_cast<volatile void *>( reinterpret_cast<const void *>(&pi->serial)), serial, NULL); - serial = atomic_load_explicit(&pi->serial, memory_order_acquire); + serial = load_const_atomic(&pi->serial, memory_order_acquire); } return serial; } |