diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/stmt.c | 22 |
1 files changed, 13 insertions, 9 deletions
@@ -1709,15 +1709,19 @@ warn_if_unused_value (exp) if (TREE_NO_UNUSED_WARNING (exp)) return 0; /* Assignment to a cast usually results in a cast of a modify. - Don't complain about that. */ - if (TREE_CODE (TREE_OPERAND (exp, 0)) == MODIFY_EXPR) - return 0; - /* Sometimes it results in a cast of a cast of a modify. - Don't complain about that. */ - if ((TREE_CODE (TREE_OPERAND (exp, 0)) == CONVERT_EXPR - || TREE_CODE (TREE_OPERAND (exp, 0)) == NOP_EXPR) - && TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0)) == MODIFY_EXPR) - return 0; + Don't complain about that. There can be an arbitrary number of + casts before the modify, so we must loop until we find the first + non-cast expression and then test to see if that is a modify. */ + { + tree tem = TREE_OPERAND (exp, 0); + + while (TREE_CODE (tem) == CONVERT_EXPR || TREE_CODE (tem) == NOP_EXPR) + tem = TREE_OPERAND (tem, 0); + + if (TREE_CODE (tem) == MODIFY_EXPR) + return 0; + } + /* ... fall through ... */ default: /* Referencing a volatile value is a side effect, so don't warn. */ |