diff --git a/kernel/yosys.cc b/kernel/yosys.cc
index 20f9791c6..57433d0d9 100644
--- a/kernel/yosys.cc
+++ b/kernel/yosys.cc
@@ -55,7 +55,7 @@
 #  include <glob.h>
 #endif
 
-#ifdef __FreeBSD__
+#if defined(__FreeBSD__) || defined(__NetBSD__)
 #  include <sys/sysctl.h>
 #endif
 
@@ -901,10 +901,14 @@ std::string proc_self_dirname()
 		buflen--;
 	return std::string(path, buflen);
 }
-#elif defined(__FreeBSD__)
+#elif defined(__FreeBSD__) || defined(__NetBSD__)
 std::string proc_self_dirname()
 {
+#ifdef __NetBSD__
+	int mib[4] = {CTL_KERN, KERN_PROC_ARGS, getpid(), KERN_PROC_PATHNAME};
+#else
 	int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
+#endif
 	size_t buflen;
 	char *buffer;
 	std::string path;