diff --git a/compiler-rt/lib/asan/asan_interceptors.cpp b/compiler-rt/lib/asan/asan_interceptors.cpp
index fc7c5b7b8fbfa..876682c3b6b3a 100644
--- a/compiler-rt/lib/asan/asan_interceptors.cpp
+++ b/compiler-rt/lib/asan/asan_interceptors.cpp
@@ -251,7 +251,7 @@ INTERCEPTOR(int, pthread_create, void *thread, void *attr,
 
   u32 current_tid = GetCurrentTidOrInvalid();
 
-  __sanitizer_sigset_t sigset;
+  __sanitizer_sigset_t sigset = {};
 #    if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \
         SANITIZER_SOLARIS
   ScopedBlockSignals block(&sigset);