diff --git a/internal/cbm/lsp/cs_lsp.c b/internal/cbm/lsp/cs_lsp.c
index c5ee1a87b..023a963af 100644
--- a/internal/cbm/lsp/cs_lsp.c
+++ b/internal/cbm/lsp/cs_lsp.c
@@ -3883,7 +3883,9 @@ CBMTypeRegistry *cbm_cs_build_cross_registry(CBMArena *arena, CBMLSPDef *defs, i
     }
     cs_register_lsp_defs(arena, reg, cs, type_count);
     cbm_registry_finalize(reg);
-    cs_register_lsp_defs(arena, reg, cs + type_count, total - type_count);
+    if (total > type_count) { /* cs is NULL for an empty corpus: no offset */
+        cs_register_lsp_defs(arena, reg, cs + type_count, total - type_count);
+    }
     cbm_registry_finalize(reg);
     reg->read_only = true; /* seal: shared Tier-2 registry is read-only during resolve */
     return reg;
diff --git a/internal/cbm/lsp/java_lsp.c b/internal/cbm/lsp/java_lsp.c
index 2b518d890..cf221f06e 100644
--- a/internal/cbm/lsp/java_lsp.c
+++ b/internal/cbm/lsp/java_lsp.c
@@ -3879,7 +3879,9 @@ CBMTypeRegistry *cbm_java_build_cross_registry(CBMArena *arena, CBMLSPDef *defs,
     }
     cbm_java_register_lsp_defs(arena, reg, jvm, type_count);
     cbm_registry_finalize(reg);
-    cbm_java_register_lsp_defs(arena, reg, jvm + type_count, total - type_count);
+    if (total > type_count) { /* jvm is NULL for an empty corpus: no offset */
+        cbm_java_register_lsp_defs(arena, reg, jvm + type_count, total - type_count);
+    }
     cbm_registry_finalize(reg);
     reg->read_only = true; /* seal: shared Tier-2 registry is read-only during resolve */
     return reg;