diff --git a/cmake/modules/ConfigSetup.cmake b/cmake/modules/ConfigSetup.cmake
index 266e3a3..3d4cf5f 100644
--- a/cmake/modules/ConfigSetup.cmake
+++ b/cmake/modules/ConfigSetup.cmake
@@ -64,6 +64,7 @@
 check_symbol_exists(strsignal "string.h" HAVE_STRSIGNAL)
 
 # Checks for include files
+check_include_file(fcntl.h HAVE_FCNTL_H)
 check_include_file(dlfcn.h HAVE_DLFCN_H)
 check_include_file(inttypes.h HAVE_INTTYPES_H)
 check_include_file(link.h HAVE_LINK_H)
@@ -119,6 +120,9 @@
 check_type_size("long double" HAVE_LONG_DOUBLE)
 check_type_size("long double" SIZEOF_LONG_DOUBLE)
 check_type_size("void*" SIZEOF_VOID_P)
+set(CMAKE_EXTRA_INCLUDE_FILES fcntl.h)
+check_type_size("loff_t" HAVE_LOFF_T)
+set(CMAKE_EXTRA_INCLUDE_FILES)
 
 # Check for various include files
 check_include_file(alloca.h HAVE_ALLOCA_H)
diff --git a/libgo/config.h.cmake b/libgo/config.h.cmake
index 150937e..2ec9bd2 100644
--- a/libgo/config.h.cmake
+++ b/libgo/config.h.cmake
@@ -5,6 +5,7 @@
 #include "llvm/Config/config.h"
 
 /* Header files */
+#cmakedefine HAVE_FCNTL_H
 #cmakedefine HAVE_LINUX_ETHER_H
 #cmakedefine HAVE_LINUX_FILTER_H
 #cmakedefine HAVE_LINUX_FS_H
@@ -162,4 +163,7 @@
 /* Define to 1 if you have the `strsignal' function. */
 #cmakedefine HAVE_STRSIGNAL 1
 
+/* Define to 1 if you have the `loff_t` type. */
+#cmakedefine HAVE_LOFF_T
+
 #endif