diff --git a/src/common/android/breakpad_getcontext.S b/src/common/android/breakpad_getcontext.S
index b41cb05c..86ef8daf 100644
--- a/src/common/android/breakpad_getcontext.S
+++ b/src/common/android/breakpad_getcontext.S
@@ -90,6 +90,9 @@ breakpad_getcontext:
 
 #elif defined(__aarch64__)
 
+#define  _NSIG                       64
+#define  __NR_rt_sigprocmask         135
+
   .text
   .global breakpad_getcontext
   .hidden breakpad_getcontext
diff --git a/src/common/android/breakpad_getcontext_unittest.cc b/src/common/android/breakpad_getcontext_unittest.cc
index c1b69c25..14d7927a 100644
--- a/src/common/android/breakpad_getcontext_unittest.cc
+++ b/src/common/android/breakpad_getcontext_unittest.cc
@@ -33,11 +33,24 @@
 #include "common/android/ucontext_constants.h"
 
 TEST(AndroidUContext, GRegsOffset) {
-#ifdef __arm__
+#if defined(__arm__)
   // There is no gregs[] array on ARM, so compare to the offset of
   // first register fields, since they're stored in order.
   ASSERT_EQ(static_cast<size_t>(MCONTEXT_GREGS_OFFSET),
             offsetof(ucontext_t,uc_mcontext.arm_r0));
+#elif defined(__aarch64__)
+  // There is no gregs[] array on ARM, so compare to the offset of
+  // first register fields, since they're stored in order.
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_GREGS_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.regs[0]));
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_SP_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.sp));
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_PC_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.pc));
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_PSTATE_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.pstate));
+  ASSERT_EQ(static_cast<size_t>(MCONTEXT_EXTENSION_OFFSET),
+            offsetof(ucontext_t,uc_mcontext.__reserved));
 #elif defined(__i386__)
   ASSERT_EQ(static_cast<size_t>(MCONTEXT_GREGS_OFFSET),
             offsetof(ucontext_t,uc_mcontext.gregs));
diff --git a/src/common/android/include/sys/ucontext.h b/src/common/android/include/sys/ucontext.h
index 8bd5877f..bfc22c44 100644
--- a/src/common/android/include/sys/ucontext.h
+++ b/src/common/android/include/sys/ucontext.h
@@ -72,6 +72,7 @@ typedef struct ucontext {
   struct ucontext *uc_link;
   stack_t uc_stack;
   sigset_t uc_sigmask;
+  char __padding[128 - sizeof(sigset_t)];
   mcontext_t uc_mcontext;
 } ucontext_t;
 
diff --git a/src/common/android/ucontext_constants.h b/src/common/android/ucontext_constants.h
index 4b00ae23..251718c3 100644
--- a/src/common/android/ucontext_constants.h
+++ b/src/common/android/ucontext_constants.h
@@ -49,11 +49,11 @@
 
 #define  UCONTEXT_SIGMASK_OFFSET     40
 
-#define  MCONTEXT_GREGS_OFFSET       56
-#define  MCONTEXT_SP_OFFSET          304
-#define  MCONTEXT_PC_OFFSET          312
-#define  MCONTEXT_PSTATE_OFFSET      320
-#define  MCONTEXT_EXTENSION_OFFSET   336
+#define  MCONTEXT_GREGS_OFFSET       184
+#define  MCONTEXT_SP_OFFSET          432
+#define  MCONTEXT_PC_OFFSET          440
+#define  MCONTEXT_PSTATE_OFFSET      448
+#define  MCONTEXT_EXTENSION_OFFSET   464
 
 #define  FPSIMD_MAGIC                0x46508001
 
@@ -67,9 +67,6 @@
 #define  REGISTER_SIZE               8
 #define  SIMD_REGISTER_SIZE          16
 
-#define  _NSIG                       64
-#define  __NR_rt_sigprocmask         135
-
 #elif defined(__i386__)
 
 #define  MCONTEXT_GREGS_OFFSET     20