diff --git a/kernel/yosys.cc b/kernel/yosys.cc
index 8da57fd4..42ccf13f 100644
--- a/kernel/yosys.cc
+++ b/kernel/yosys.cc
@@ -622,7 +622,7 @@ struct TclPass : public Pass {
 } TclPass;
 #endif
 
-#if defined(__linux__)
+#if defined(__linux__) || defined(__CYGWIN__)
 std::string proc_self_dirname()
 {
 	char path[PATH_MAX];