model-checker: Don't discard error states.

Even if a state with an error is a duplicate, we don't want to discard it,
because then we lose information about bugs.

diff --git a/src/libpspp/model-checker.c b/src/libpspp/model-checker.c
index 6068713c812b923dece90fb47cf9b8e6838223f5..62eef04ee5f9fdead6675e5cea29df3c62ba5b17 100644 (file)
--- a/src/libpspp/model-checker.c
+++ b/src/libpspp/model-checker.c
@@ -1057,7 +1057,7 @@ mc_include_state (struct mc *mc)
 bool
 mc_discard_dup_state (struct mc *mc, unsigned int hash)
 {
-  if (mc->options->hash_bits > 0)
+  if (!mc->state_error && mc->options->hash_bits > 0)
     {
       hash &= (1u << mc->options->hash_bits) - 1;
       if (TEST_BIT (mc->hash, hash))