Merge branch 'jk/tighten-alloc'

Update various codepaths to avoid manually-counted malloc().

* jk/tighten-alloc: (22 commits)
  ewah: convert to REALLOC_ARRAY, etc
  convert ewah/bitmap code to use xmalloc
  diff_populate_gitlink: use a strbuf
  transport_anonymize_url: use xstrfmt
  git-compat-util: drop mempcpy compat code
  sequencer: simplify memory allocation of get_message
  test-path-utils: fix normalize_path_copy output buffer size
  fetch-pack: simplify add_sought_entry
  fast-import: simplify allocation in start_packfile
  write_untracked_extension: use FLEX_ALLOC helper
  prepare_{git,shell}_cmd: use argv_array
  use st_add and st_mult for allocation size computation
  convert trivial cases to FLEX_ARRAY macros
  use xmallocz to avoid size arithmetic
  convert trivial cases to ALLOC_ARRAY
  convert manual allocations to argv_array
  argv-array: add detach function
  add helpers for allocating flex-array structs
  harden REALLOC_ARRAY and xcalloc against size_t overflow
  tree-diff: catch integer overflow in combine_diff_path allocation
  ...

revision.c

@@ -484,7 +484,7 @@ struct treesame_state {
 static struct treesame_state *initialise_treesame(struct rev_info *revs, struct commit *commit)
 {
 	unsigned n = commit_list_count(commit->parents);
-	struct treesame_state *st = xcalloc(1, sizeof(*st) + n);
+	struct treesame_state *st = xcalloc(1, st_add(sizeof(*st), n));
 	st->nparents = n;
 	add_decoration(&revs->treesame, &commit->object, st);
 	return st;