diff --git a/fns.h b/fns.h
index bfe8c47616..b84c228977 100644
--- a/fns.h
+++ b/fns.h
@@ -1,5 +1,4 @@
 // <signal.h>
-/*
 void sigaction();
 void sigemptyset();
 
@@ -9,4 +8,3 @@ void* memmove();
 void* memset();
 unsigned long strlen(const char*);
 char* strerror(int);
-*/
diff --git a/vlib/compiler/cheaders.v b/vlib/compiler/cheaders.v
index 313c4eaa3a..621df68b91 100644
--- a/vlib/compiler/cheaders.v
+++ b/vlib/compiler/cheaders.v
@@ -7,7 +7,6 @@ CommonCHeaders = '
 #include <stdio.h>  // TODO remove all these includes, define all function signatures and types manually
 #include <stdlib.h>
 #include "fns.h"
-#include <signal.h>
 #include <stdarg.h> // for va_list
 #include <inttypes.h>  // int64_t etc
 #include <string.h> // memcpy
@@ -23,9 +22,6 @@ CommonCHeaders = '
 #endif
 #endif
 
-#if defined(__CYGWIN__) && !defined(_WIN32)
-#error Cygwin is not supported, please use MinGW or Visual Studio.
-#endif
 
 #ifdef __linux__
 #include <sys/types.h>