Issue #7117 (backport py3k float repr) continued:
 - add double endianness detection to configure script
 - add configure-time check to see whether we can use inline
   assembly to get and set x87 control word in configure script
 - add functions to get and set x87 control word in Python/pymath.c
 - add pyport.h logic to determine whether it's safe to use the
   short float repr or not
diff --git a/pyconfig.h.in b/pyconfig.h.in
index 6bc9d7f..ff1734e 100644
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -18,6 +18,18 @@
 /* Define if you have the Mach cthreads package */
 #undef C_THREADS
 
+/* Define if C doubles are 64-bit IEEE 754 binary format, stored in ARM
+   mixed-endian order (byte order 45670123) */
+#undef DOUBLE_IS_ARM_MIXED_ENDIAN_IEEE754
+
+/* Define if C doubles are 64-bit IEEE 754 binary format, stored with the most
+   significant byte first */
+#undef DOUBLE_IS_BIG_ENDIAN_IEEE754
+
+/* Define if C doubles are 64-bit IEEE 754 binary format, stored with the
+   least significant byte first */
+#undef DOUBLE_IS_LITTLE_ENDIAN_IEEE754
+
 /* Define if --enable-ipv6 is specified */
 #undef ENABLE_IPV6
 
@@ -240,6 +252,10 @@
 /* Define to 1 if you have the `gamma' function. */
 #undef HAVE_GAMMA
 
+/* Define if we can use gcc inline assembler to get and set x87 control word
+   */
+#undef HAVE_GCC_ASM_FOR_X87
+
 /* Define if you have the getaddrinfo function. */
 #undef HAVE_GETADDRINFO