Fix a segfault in the case where the entire recursive scan covers

[sgt/agedu] / trie.c

diff --git a/trie.c b/trie.c
index 345756f..ddadddb 100644 (file)
--- a/trie.c
+++ b/trie.c
@@ -218,7 +218,8 @@ static off_t triebuild_unwind(triebuild *tb, int targetdepth, int *outcount)
     while (depth > targetdepth) {
        int odepth = depth;
        while (depth > targetdepth &&
-              (depth-1 > tb->switchsize || tb->switches[depth-1].len == 0))
+              (depth-1 > tb->switchsize || !tb->switches ||
+               tb->switches[depth-1].len == 0))
            depth--;
        if (odepth > depth) {
            /*