md_opener_stack: Mark the default branch of switch as unreachable. We were returning NULL previously, but that would lead to a crash anyway; all callsites expect to get their respective stack anyway and anything else would mean we are internally broken.
diff --git a/src/md4c.c b/src/md4c.c
index 0907286..3093e2a 100644
--- a/src/md4c.c
+++ b/src/md4c.c
@@ -2555,7 +2555,7 @@ md_opener_stack(MD_CTX* ctx, int mark_index)
case _T('!'):
case _T('['): return &BRACKET_OPENERS;
- default: return NULL;
+ default: MD_UNREACHABLE();
}
}