--- mozilla-esr38/js/src/jstypes.h.x32fix	2017-03-21 08:17:52.446161040 +0100
+++ mozilla-esr38/js/src/jstypes.h	2017-03-21 08:18:23.531014466 +0100
@@ -142,7 +142,7 @@
 # endif
 #elif defined(__GNUC__)
 /* Additional GCC defines are when running on Solaris, AIX, and HPUX */
-# if defined(__x86_64__) || defined(__sparcv9) || \
+# if (defined(__x86_64__) && !defined(__ILP32__)) || defined(__sparcv9) || \
         defined(__64BIT__) || defined(__LP64__)
 #  define JS_64BIT
 # endif