diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_syscalls.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_syscalls.inc
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common_syscalls.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_syscalls.inc
@@ -1375,13 +1375,14 @@
 
 POST_SYSCALL(io_setup)(long res, long nr_reqs, void **ctx) {
   if (res >= 0) {
-    if (ctx)
+    if (ctx) {
       POST_WRITE(ctx, sizeof(*ctx));
-    // (*ctx) is actually a pointer to a kernel mapped page, and there are
-    // people out there who are crazy enough to peek into that page's 32-byte
-    // header.
-    if (*ctx)
-      POST_WRITE(*ctx, 32);
+      // (*ctx) is actually a pointer to a kernel mapped page, and there are
+      // people out there who are crazy enough to peek into that page's 32-byte
+      // header.
+      if (*ctx)
+        POST_WRITE(*ctx, 32);
+    }
   }
 }