--- a/gcc/caller-save.c
+++ b/gcc/caller-save.c
@@ -155,7 +155,7 @@
       cached_reg_save_code[reg][mode] = -1;
       cached_reg_restore_code[reg][mode] = -1;
     }
-  gcc_assert (cached_reg_save_code[reg][mode]);
+  gcc_assert (cached_reg_save_code[reg][mode] != -1);
   return cached_reg_save_code[reg][mode];
 }