Some more info:

(gdb) frame 3
#3  0x000000000087c565 in row_search_for_mysql (buf=0x7fff8800ff10 "\377\344:", mode=2,
    prebuilt=0x7fff880107d8, match_mode=1, direction=0)
    at /media/Tintin/Work/code/percona-xtradb-cluster/release-5.5.31/Percona-Server/storage/innobase/row/row0sel.c:3738
3738                                   if (!row_sel_store_mysql_rec(buf, prebuilt,

(gdb) info locals
index = 0x7fff98016748
search_tuple = 0x7fff88010af8
pcur = 0x7fff88010848
trx = 0x7fff0c045b48
clust_index = <optimized out>
rec = 0x7fffd42fa6af ""
result_rec = <optimized out>
clust_rec = <optimized out>
err = 10
unique_search = 1
unique_search_from_clust_index = 1
mtr_has_extra_clust_latch = 0
moves_up = 0
set_also_gap_locks = 1
did_semi_consistent_read = 0
i = <optimized out>
should_release = <optimized out>
next_offs = <optimized out>
same_user_rec = 4
mtr = {
  state = 12231,
  memo = {
    heap = 0x0,
    used = 0,
    data = "*&\203\000\000\000\000\000\026Ь\000\000\000\000\000\230\346\254\000\000\000\000\000\n\000\000\200\000\000\000\000\060\a\017\254\377\177\000\000\000\000\000\000\000\000\000\000\240\t\000\f\377\177\000\000\300\003\017\254\377\177\000\000\240\t\000\f\377\177\000\000\320\003\017\254\377\177\000\000\210\066\017\254\377\177\000\000p\001\017\254\377\177\000\000\271C\250\000\000\000\000\000\260\003\017\254\377\177\000\000\240\t\000\f\377\177\000\000\300\003\017\254\377\177\000\000\240\t\000\f\377\177\000\000`\004\017\254\377\177\000\000\210\066\017\254\377\177\000\000\260\001\017\254\377\177\000\000\271C\250\000\000\000\000\000dQ\000\f\377\177\000\000\240\t\000\f\377\177\000\000\000\004\017\254\377\177\000\000\256e\250\000\000\000\000\000\250"...,
    base = {
      count = 140733394717088,
      start = 0x7fffac0f0550,
      end = 0xa865ae <_db_return_+134>
    },
    list = {
      prev = 0x7fffac0f05b0,
      next = 0xf0
    },
    buf_end = 0,
    magic_n = 375767
  },
  log = {
    heap = 0x0,
    used = 0,
    data = "\220\005\017\254\377\177\000\000\256e\250\000\000\000\000\000\220\003\017\254\377\177\000\000\240\t\000\f\377\177\000\000\360\005\017\254\377\177\000\000\210\066\017\254\377\177\000\000\220\003\017\254\377\177\000\000\271C\250\000\000\000\000\000\240\003\017\254\377\177\000\000\240\t\000\f\377\177\000\000\340\005\017\254\377\177\000\000\256e\250\000\000\000\000\000\360\005\017\254\377\177\000\000\240\t\000\f\377\177\000\000\360\006\017\254\377\177\000\000\210\066\017\254\377\177\000\000\340\003\017\254\377\177\000\000\271C\250\000\000\000\000\000`\006\017\254\377\177\000\000\240\t\000\f\377\177\000\000p\006\017\254\377\177\000\000\210\066\017\254\377\177\000\000\020\004\017\254\377\177\000\000\271C\250\000\000\000\000\000P\006\017\254\377\177\000\000"...,
    base = {
      count = 0,
      start = 0x7fff88010b48,
      end = 0x7fff980169a0
    },
    list = {
      prev = 0x0,
      next = 0x7fffac0f0600
    },
    buf_end = 0,
    magic_n = 375767
  },
  inside_ibuf = 0,
  modifications = 0,
  made_dirty = 0,
  n_log_recs = 0,
  n_freed_pages = 0,
  log_mode = 21,
  start_lsn = 140735475145064,
  end_lsn = 1,
  magic_n = 54551
}
heap = 0x0
offsets_ = {100, 6, 140736753280687, 140735743616840, 2147483655, 4, 10, 17, 21, 141, 201, 0, 0,
  140733394717088, 140736080052400, 140736080066184, 140736080051792, 11027385, 0, 140733394717088,
  140736080052384, 11036078, 0, 140733394717088, 140736080052480, 140736080066184, 140736080051872,
  11027385, 0, 140733394717088, 140736080052464, 11036078, 0, 7637, 0, 0, 140736080053056, 6674625, 0,
  19145632, 19146168, 0, 19146144, 12884901888, 0, 0, 0, 0, 0, 0, 140737311254224, 0, 0, 0,
  140736080052048, 140733394717088, 140736080052752, 140736080066184, 140736080052128, 11027385, 0,
  140733394717088, 140736080052720, 11036078, 0, 278, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 140736080052464,
  8548002, 140736080052400, 0, 0, 4, 80, 140733394717088, 7181631648, 369, 2, 140735475156952,
  140735743616840, 140733462086731, 140735475140960, 0, 140735475156408, 0, 140736080052464, 8586297,
  12014576, 12020656, 2147483659, 140735475140960}
offsets = 0x7fffac0efdb0
table_lock_waited = 0
problematic_use = 0
(gdb) list
3733                                    row_sel_try_search_shortcut_for_mysql().
3734                                    The latch will not be released until
3735                                    mtr_commit(&mtr). */
3736                                    ut_ad(!rec_get_deleted_flag(rec, comp));
3737
3738                                    if (!row_sel_store_mysql_rec(buf, prebuilt,
3739                                                                 rec, FALSE,
3740                                                                 offsets)) {
3741                                            /* Only fresh inserts may contain
3742