git-pickaxe: tighten sanity checks.

When compiled for debugging, make sure that refcnt sanity check
code detects underflows in origin reference counting.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/builtin-pickaxe.c b/builtin-pickaxe.c
index 3e7277da21cdf4c94a0056e1e9a404c383a5f6b8..82868328ac1fb6b951e2124db7a8563365fe34e3 100644 (file)
--- a/builtin-pickaxe.c
+++ b/builtin-pickaxe.c
@@ -973,7 +973,9 @@ static void assign_blame(struct scoreboard *sb, struct rev_info *revs, int opt)
                        if (!cmp_suspect(ent->suspect, suspect))
                                ent->guilty = 1;
                origin_decref(suspect);
-               coalesce(sb);
+
+               if (DEBUG) /* sanity */
+                       sanity_check_refcnt(sb);
        }
 }
 
@@ -1341,11 +1343,14 @@ static void sanity_check_refcnt(struct scoreboard *sb)
        struct blame_entry *ent;
 
        for (ent = sb->ent; ent; ent = ent->next) {
-               /* first mark the ones that haven't been checked */
+               /* Nobody should have zero or negative refcnt */
+               if (ent->suspect->refcnt <= 0)
+                       baa = 1;
+       }
+       for (ent = sb->ent; ent; ent = ent->next) {
+               /* Mark the ones that haven't been checked */
                if (0 < ent->suspect->refcnt)
                        ent->suspect->refcnt = -ent->suspect->refcnt;
-               else if (!ent->suspect->refcnt)
-                       baa = 1;
        }
        for (ent = sb->ent; ent; ent = ent->next) {
                /* then pick each and see if they have the the
@@ -1357,7 +1362,7 @@ static void sanity_check_refcnt(struct scoreboard *sb)
 
                if (0 < suspect->refcnt)
                        continue;
-               suspect->refcnt = -suspect->refcnt;
+               suspect->refcnt = -suspect->refcnt; /* Unmark */
                for (found = 0, e = sb->ent; e; e = e->next) {
                        if (e->suspect != suspect)
                                continue;