diff --git a/multiarc/CMakeLists.txt b/multiarc/CMakeLists.txt
index b7972a5ac..17fbd913b 100644
--- a/multiarc/CMakeLists.txt
+++ b/multiarc/CMakeLists.txt
@@ -60,6 +60,7 @@ set(SOURCES
         src/formats/7z/C/CpuArch.c
         src/formats/7z/C/LzFind.c
         src/formats/7z/C/LzFindMt.c
+        src/formats/7z/C/Threads.c
         src/formats/7z/C/Ppmd7.c
         src/formats/7z/C/Lzma2Enc.c
         src/formats/7z/C/Sha256.c