(ITS#8784) SIGBUS in mdb_page_touch

[balaret@gmail.com]

Full_Name: Sergey Z
Version: LMDB_0.9.19
OS: Android
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (2620:119:5001:2242:9215:2763:ff1b:ae35)


Hey guys,

We are using LMDB 0.9.19 in our Android project and sometimes we are getting
SIGBUS in mdb_page_touch(). We can't reproduce this issue on our side but we
have plenty of crash reports from our users (about 400 daily):

SIGBUS
	libLMDBAndroid.so.mdb_page_touch ( mdb .c :2412)
	libLMDBAndroid.so.mdb_page_search ( mdb .c :5610)
	libLMDBAndroid.so.mdb_freelist_save ( mdb .c :3128)
	libLMDBAndroid.so.mdb_txn_commit ( mdb .c :3606)

This is probably a platform specific issue because 95% of crashes happened on
Android 7.0. 

I would greatly appreciate if you help to shed a light on this - any ideas what
might goes wrong or what might cause such an issue.

Thank you,
Sergey