diff --git a/compiler-rt/lib/fuzzer/FuzzerLoop.cpp b/compiler-rt/lib/fuzzer/FuzzerLoop.cpp
--- a/compiler-rt/lib/fuzzer/FuzzerLoop.cpp
+++ b/compiler-rt/lib/fuzzer/FuzzerLoop.cpp
@@ -275,7 +275,7 @@
   assert(Options.UnitTimeoutSec > 0);
   // In Windows Alarm callback is executed by a different thread.
   // NetBSD's current behavior needs this change too.
-#if !LIBFUZZER_WINDOWS && !LIBFUZZER_NETBSD
+#if !LIBFUZZER_WINDOWS && !LIBFUZZER_NETBSD && !LIBFUZZER_FUCHSIA
   if (!InFuzzingThread())
     return;
 #endif