diff --git a/libc/test/src/__support/threads/linux/CMakeLists.txt b/libc/test/src/__support/threads/linux/CMakeLists.txt
index ce9becb923c3a..4299a5617b8ff 100644
--- a/libc/test/src/__support/threads/linux/CMakeLists.txt
+++ b/libc/test/src/__support/threads/linux/CMakeLists.txt
@@ -9,4 +9,5 @@ add_libc_test(
     libc.src.sys.mman.mmap
     libc.src.sys.mman.munmap
     libc.src.stdlib.exit
+    libc.hdr.signal_macros
 )
diff --git a/libc/test/src/__support/threads/linux/raw_mutex_test.cpp b/libc/test/src/__support/threads/linux/raw_mutex_test.cpp
index aff6c8be0cb1b..918f5d35c94f4 100644
--- a/libc/test/src/__support/threads/linux/raw_mutex_test.cpp
+++ b/libc/test/src/__support/threads/linux/raw_mutex_test.cpp
@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "hdr/signal_macros.h"
 #include "include/llvm-libc-macros/linux/time-macros.h"
 #include "src/__support/CPP/atomic.h"
 #include "src/__support/OSUtil/syscall.h"