libctf: dedup: describe 'citer'

The distinction between the citer and citers variables in
ctf_dedup_rhash_type is somewhat opaque (it's a micro-optimization to avoid
having to allocate entire sets when we know in advance that we'll only have
to store one value).  Add a comment.

libctf/
	* ctf-dedup.c (ctf_dedup_rhash_type): Comment on citers variables.

diff --git a/libctf/ctf-dedup.c b/libctf/ctf-dedup.c
index 2767904c75fdf5f5cc15f0e732cfdcd23f6bbdb3..93a70d60f937cf70d67f3305e257a4714c5ad88b 100644 (file)
--- a/libctf/ctf-dedup.c
+++ b/libctf/ctf-dedup.c
@@ -584,6 +584,8 @@ ctf_dedup_rhash_type (ctf_dict_t *fp, ctf_dict_t *input, ctf_dict_t **inputs,
   const char *whaterr;
   int err = 0;
 
+  /* "citer" is for types that reference only one other type: "citers" can store
+     many of them, but is more expensive to both populate and traverse.  */
   const char *citer = NULL;
   ctf_dynset_t *citers = NULL;