1 files changed, 12 insertions, 1 deletions
diff --git a/src/gtest-death-test.cc b/src/gtest-death-test.cc
index 36a2e3a..de50ba7 100644
--- a/src/gtest-death-test.cc
+++ b/src/gtest-death-test.cc
@@ -1062,8 +1062,19 @@ static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {
     void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
                              MAP_ANON | MAP_PRIVATE, -1, 0);
     GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);
+
+    // Maximum stack alignment in bytes:  For a downward-growing stack, this
+    // amount is subtracted from size of the stack space to get an address
+    // that is within the stack space and is aligned on all systems we care
+    // about.  As far as I know there is no ABI with stack alignment greater
+    // than 64.  We assume stack and stack_size already have alignment of
+    // kMaxStackAlignment.
+    const size_t kMaxStackAlignment = 64;
     void* const stack_top =
-        static_cast<char*>(stack) + (stack_grows_down ? stack_size : 0);
+        static_cast<char*>(stack) +
+            (stack_grows_down ? stack_size - kMaxStackAlignment : 0);
+    GTEST_DEATH_TEST_CHECK_(stack_size > kMaxStackAlignment &&
+        reinterpret_cast<intptr_t>(stack_top) % kMaxStackAlignment == 0);
 
     child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args);