> On 2016-09-14, at 17:56, Jeff King <peff@xxxxxxxx> wrote: > > On Wed, Sep 14, 2016 at 05:42:29PM -0700, Jonathon Mah wrote: > >> Hi git, I've been seeing git segfault over the past few days. I'm on Mac OS X 10.12, 64-bit, compiling with clang (Apple LLVM version 8.0.0 (clang-800.0.40)). >> [...] >> Bisect says: >> >> 8261e1f139db3f8aa6f9fd7d98c876cbeb0f927c is the first bad commit >> commit 8261e1f139db3f8aa6f9fd7d98c876cbeb0f927c >> Author: Jeff King <peff@xxxxxxxx> >> Date: Mon Aug 22 18:00:07 2016 -0400 >> >> delta_base_cache: use hashmap.h > > Have you tried with the patch in: > > http://public-inbox.org/git/20160912164616.vg33kldazuthff3d@xxxxxxxxxxxxxxxxxxxxx/ > > ? All the examples I've tried work when I use that. Thanks! >> $ lldb /Users/jmah/Documents/Streams/git/git-log -- -u >> (lldb) target create "/Users/jmah/Documents/Streams/git/git-log" >> Current executable set to '/Users/jmah/Documents/Streams/git/git-log' (x86_64). >> (lldb) settings set -- target.run-args "-u" >> (lldb) process launch -o /dev/null >> Process 92815 launched: '/Users/jmah/Documents/Streams/git/git-log' (x86_64) >> Process 92815 stopped >> * thread #1: tid = 0x1c30677, 0x00000001001bba80 git-log`release_delta_base_cache(ent=0xffffffffffffffd0) + 16 at sha1_file.c:2171, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x10) >> frame #0: 0x00000001001bba80 git-log`release_delta_base_cache(ent=0xffffffffffffffd0) + 16 at sha1_file.c:2171 >> 2168 >> 2169 static inline void release_delta_base_cache(struct delta_base_cache_entry *ent) >> 2170 { >> -> 2171 free(ent->data); >> 2172 detach_delta_base_cache_entry(ent); > > The problems I saw with valgrind weren't here, but would explain this. > We free() the previous node, then walk forward from its "next" pointer. > On my Linux box, that happens to work, but we could be feeding total > junk to the list pointer, which would meant ent->data is junk, and > free() notices. > > -Peff