diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc b/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
index 80009ea4e914..782e520e69b5 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
@@ -1156,8 +1156,12 @@ void internal_join_thread(void *th) {}
 #endif
 
 bool GetSigContextWriteFlag(void *context) {
+#if defined(__x86_64__) || defined(__i386__)
   ucontext_t *ucontext = (ucontext_t*)context;
   return ucontext->uc_mcontext.gregs[REG_ERR] & 2;
+#else
+  return false;  // FIXME: Implement.
+#endif
 }
 
 void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
diff --git a/compiler-rt/test/asan/TestCases/Linux/segv_read_write.c b/compiler-rt/test/asan/TestCases/Linux/segv_read_write.c
index 841037137378..db6726cd3741 100644
--- a/compiler-rt/test/asan/TestCases/Linux/segv_read_write.c
+++ b/compiler-rt/test/asan/TestCases/Linux/segv_read_write.c
@@ -1,6 +1,7 @@
 // RUN: %clangxx_asan -O0 %s -o %t
 // RUN: not %run %t       2>&1 | FileCheck %s --check-prefix=READ
 // RUN: not %run %t write 2>&1 | FileCheck %s --check-prefix=WRITE
+// REQUIRES: x86_64-supported-target
 
 static volatile int sink;
 __attribute__((noinline)) void Read(int *ptr) { sink = *ptr; }