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Overview
Comment:Turns out this is an aliasing bug in SQLite, not a GCC bug. Was: Work-around for what appears to be another GCC bug - this one for GCC 8.3.0 on ARM. See the SQLite forum post for discussion.
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SHA3-256: 40c44d38104dfcb688155d1172cb172c1bb1d90d54ecf0cfd89f0810c1b515d9
User & Date: drh 2020-07-23 20:37:39
Original Comment: Work-around for what appears to be another GCC bug - this one for GCC 8.3.0 on ARM. See the SQLite forum post for discussion.
Context
2020-07-23
20:37
Turns out this is an aliasing bug in SQLite, not a GCC bug. Was: Work-around for what appears to be another GCC bug - this one for GCC 8.3.0 on ARM. See the SQLite forum post for discussion. (Closed-Leaf check-in: 40c44d38 user: drh tags: mistake)
18:03
Add the OMIT_ZLIB compile-time option to sessionfuzz.c. (Originally checked into the wrong branch.) (check-in: 6019bf8a user: drh tags: trunk)
Changes
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Changes to src/memjournal.c.

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  p->zJournal = zName;
  p->pVfs = pVfs;
  return SQLITE_OK;
}

/*
** Open an in-memory journal file.


















*/
void sqlite3MemJournalOpen(sqlite3_file *pJfd){
  sqlite3JournalOpen(0, 0, pJfd, 0, -1);

}

#if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
 || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
/*
** If the argument p points to a MemJournal structure that is not an 
** in-memory-only journal file (i.e. is one that was opened with a +ve








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  p->zJournal = zName;
  p->pVfs = pVfs;
  return SQLITE_OK;
}

/*
** Open an in-memory journal file.
**
** The SQLITE_NOINLINE is to work-around for what appears to be a bug in GCC
** (version 8.3.0 tested) for ARM.  The GCC optimizer apparently believes
** that the call to this routine from pager_open_journal() cannot change
** the value of pJfd->pMethods.  Hence it caches the prior NULL value of
** pJfd->pMethods and reuses that NULL it inside a subsequent assert(),
** which then fails.  See
**
**    https://bugs.gentoo.org/685874
**    https://bugs.gentoo.org/733092
**    https://sqlite.org/forum/forumpost/d44eb2fc44
**
** The problem only appears for -O2.  -O1, -Os, and -O0 all work fine.  The
** Gentoo bugs above indicate that a similar problem exists on PPC and SPARC,
** but I have only verify the problem (and this fix) on ARM.
**
** This routine is not often called, so preventing it from being
** inlined does not impact performance.
*/
SQLITE_NOINLINE void sqlite3MemJournalOpen(sqlite3_file *pJfd){
  sqlite3JournalOpen(0, 0, pJfd, 0, -1);
  assert( pJfd->pMethods!=0 );
}

#if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
 || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
/*
** If the argument p points to a MemJournal structure that is not an 
** in-memory-only journal file (i.e. is one that was opened with a +ve
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