* st.c (unpack_entries): save table->bins and never change the table

  during unpacking. Because st_insert() may cause GC and refer the
  table, i.e. st_foreach().  [Bug #2196]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@25377 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 10 insertions, 8 deletions

diff --git a/st.c b/st.c
index 1974113fb2..fe8913bcc5 100644
--- a/st.c
+++ b/st.c
@@ -418,15 +418,17 @@ unpack_entries(register st_table *table)
 {
     int i;
     struct st_table_entry *packed_bins[MAX_PACKED_NUMHASH*2];
-    int num_entries = table->num_entries;
-
-    memcpy(packed_bins, table->bins, sizeof(struct st_table_entry *) * num_entries*2);
-    table->entries_packed = 0;
-    table->num_entries = 0;
-    memset(table->bins, 0, sizeof(struct st_table_entry *) * table->num_bins);
-    for (i = 0; i < num_entries; i++) {
-        st_insert(table, (st_data_t)packed_bins[i*2], (st_data_t)packed_bins[i*2+1]);
+    st_table tmp_table = *table;
+
+    memcpy(packed_bins, table->bins, sizeof(struct st_table_entry *) * table->num_entries*2);
+    table->bins = packed_bins;
+    tmp_table.entries_packed = 0;
+    tmp_table.num_entries = 0;
+    memset(tmp_table.bins, 0, sizeof(struct st_table_entry *) * tmp_table.num_bins);
+    for (i = 0; i < table->num_entries; i++) {
+        st_insert(&tmp_table, (st_data_t)packed_bins[i*2], (st_data_t)packed_bins[i*2+1]);
     }
+    *table = tmp_table;
 }
 
 int