--- a/liboath/gl/stdio-impl.h
+++ b/liboath/gl/stdio-impl.h
@@ -71,6 +71,12 @@
 #  else
 #   define _gl_flags_file_t short
 #  endif
+#  ifdef __LP64__
+#   define _gl_file_offset_t int64_t
+#  else
+    /* see https://android.googlesource.com/platform/bionic/+/master/docs/32-bit-abi.md */
+#   define _gl_file_offset_t __kernel_off_t
+#  endif
   /* Up to this commit from 2015-10-12
      <https://android.googlesource.com/platform/bionic.git/+/f0141dfab10a4b332769d52fa76631a64741297a>
      the innards of FILE were public, and fp_ub could be defined like for OpenBSD,
@@ -96,7 +102,7 @@
                          unsigned char _nbuf[1]; \
                          struct { unsigned char *_base; size_t _size; } _lb; \
                          int _blksize; \
-                         fpos_t _offset; \
+                         _gl_file_offset_t _offset; \
                          /* More fields, not relevant here.  */ \
                        } *) fp)
 # else