diff --git a/apps/apps.h b/apps/apps.h
index 201ec03fd9..c53755a861 100644
--- a/apps/apps.h
+++ b/apps/apps.h
@@ -59,7 +59,11 @@
 #ifndef HEADER_APPS_H
 #define HEADER_APPS_H
 
+#ifdef FLAT_INC
 #include "e_os.h"
+#else
+#include "../e_os.h"
+#endif
 
 #include <openssl/buffer.h>
 #include <openssl/bio.h>
diff --git a/crypto/bf/bftest.c b/crypto/bf/bftest.c
index 42e00963e7..89b72d44bd 100644
--- a/crypto/bf/bftest.c
+++ b/crypto/bf/bftest.c
@@ -63,7 +63,11 @@
 #include <string.h>
 #include <stdlib.h>
 
+#ifdef FLAT_INC
 #include "e_os.h"
+#else
+#include "../e_os.h"
+#endif
 
 #ifdef NO_BF
 int main(int argc, char *argv[])
diff --git a/crypto/cryptlib.h b/crypto/cryptlib.h
index 390488a37d..e619a992f7 100644
--- a/crypto/cryptlib.h
+++ b/crypto/cryptlib.h
@@ -62,7 +62,11 @@
 #include <stdlib.h>
 #include <string.h>
 
+#ifdef FLAT_INC
 #include "e_os.h"
+#else
+#include "../e_os.h"
+#endif
 
 #include <openssl/crypto.h>
 #include <openssl/buffer.h>