diff --git a/tests/fortify_test.cpp b/tests/fortify_test.cpp
index cc3080d..29aba60 100644
--- a/tests/fortify_test.cpp
+++ b/tests/fortify_test.cpp
@@ -29,7 +29,7 @@
 
 #include <android-base/silent_death_test.h>
 
-#if __BIONIC__
+#if defined(__BIONIC__)
 #define ASSERT_FORTIFY(expr) ASSERT_EXIT(expr, testing::KilledBySignal(SIGABRT), "FORTIFY")
 #else
 #define ASSERT_FORTIFY(expr) ASSERT_EXIT(expr, testing::KilledBySignal(SIGABRT), "")
@@ -1014,7 +1014,7 @@
 }
 
 TEST_F(DEATHTEST, ppoll64_fortified) {
-#if __BIONIC__ // glibc doesn't have ppoll64.
+#if defined(__BIONIC__)        // glibc doesn't have ppoll64.
   nfds_t fd_count = atoi("2"); // suppress compiler optimizations
   pollfd buf[1] = {{0, POLLIN, 0}};
   // Set timeout to zero to prevent waiting in ppoll when fortify test fails.
@@ -1030,7 +1030,7 @@
 }
 
 TEST_F(DEATHTEST, open_O_TMPFILE_without_mode_fortified) {
-#if __BIONIC__ // Our glibc is too old for O_TMPFILE.
+#if defined(__BIONIC__)  // Our glibc is too old for O_TMPFILE.
   int flags = O_TMPFILE; // Fool the compiler.
   ASSERT_FORTIFY(open("", flags));
 #endif