2 files changed, 9 insertions, 0 deletions

diff --git a/firmware/SOURCES b/firmware/SOURCES
index 23c3a6dddc..7ebfba38e1 100644
--- a/firmware/SOURCES
+++ b/firmware/SOURCES
@@ -14,7 +14,9 @@ common/file.c
 common/dircache.c
 #endif
 common/disk.c
+#if !defined(SIMULATOR) || defined(__MINGW32__) || defined(__CYGWIN__)
 common/errno.c
+#endif
 common/memcmp.c
 common/memchr.c
 common/qsort.c
diff --git a/firmware/include/errno.h b/firmware/include/errno.h
index 4162f6a9ed..1843b56f1d 100644
--- a/firmware/include/errno.h
+++ b/firmware/include/errno.h
@@ -1,6 +1,12 @@
 /* errno is not a global variable, because that would make using it
    non-reentrant.  Instead, its address is returned by the function
    __errno.  */
+   
+#if defined(SIMULATOR) && !defined(__MINGW32__) && !defined(__CYGWIN__)
+
+#include "/usr/include/errno.h"  /* use the host system implementation */
+
+#else             /* use our own implementation */
 
 #ifndef _SYS_ERRNO_H_
 
@@ -132,3 +138,4 @@ extern int errno;
 #define __ELASTERROR 2000       /* Users can add values starting here */
 
 #endif /* _SYS_ERRNO_H */
+#endif /* !SIMULATOR */