On 02/22/2017 04:01 AM, Xi Ruoyao wrote:
This patch adds warning option -Wstring-plus-int for C.
gcc/ChangeLog:
2017-02-22 Xi Ruoyao <r...@stu.xidian.edu.cn>
* c/c-typeck.c (parser_build_binary_op, build_modify_expr): checking
for -Wstring-plus-int
---
gcc/c/c-typeck.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c
index 49b99b5..288d44b 100644
--- a/gcc/c/c-typeck.c
+++ b/gcc/c/c-typeck.c
@@ -3631,6 +3631,24 @@ parser_build_binary_op (location_t location, enum
tree_code code,
? arg2.original_type
: TREE_TYPE (arg2.value));
+ /* Warn about adding string literals/pointers and chars. */
+ if (warn_string_plus_int && (TREE_CODE (type1) == POINTER_TYPE ||
+ TREE_CODE (type2) == POINTER_TYPE))
Please use POINTER_TYPE_P rather than checking the underlying tree code.
This is also formatted incorrectly. It should look like this
if (warn_string_plus_int
&& (POINTER_TYPE_P (type1) || POINTER_TYPE_P (type2))
+ enum tree_code code_ptr = (TREE_CODE (type1) == POINTER_TYPE ?
+ code1 : code2);
+ tree type_ptr = (TREE_CODE (type1) == POINTER_TYPE ?
+ type1 : type2);
+ tree type_int = (TREE_CODE (type1) == POINTER_TYPE ?
+ type2 : type1) > + enum tree_code code_int =
TREE_CODE (TREE_CODE (type1)
+ == POINTER_TYPE ?
+ arg2.value : arg1.value);
Similarly, please use POINTER_TYPE_P. That will likely eliminate the
need to warp the first 3 assigments at all. The last should be line
wrapped like this:
enum tree_code code_int = (POINTER_TYPE_P (type1)
? arg2.value
: arg1.value);
Note how we bring the operator down to the new line rather than keep it
at the end of a long line.
Please also verify that instead of 8 spaces that you use tabs. I think
the assignments above are using 8 spaces rather than tabs.
@@ -5768,6 +5786,16 @@ build_modify_expr (location_t location, tree lhs, tree
lhs_origtype,
rhseval = newrhs;
}
+ /* Warn about adding string literals/pointers and chars. */
+ if (modifycode == PLUS_EXPR && warn_string_plus_int)
+ {
+ tree lhs_type1 = (lhs_origtype ? lhs_origtype :
+ TREE_TYPE (lhs));
+ tree rhs_type1 = (rhs_origtype ? rhs_origtype :
+ TREE_TYPE (rhs));
+ maybe_warn_string_plus_int (location, lhs_type1, rhs_type1,
+ TREE_CODE (lhs), TREE_CODE (rhs));
+ }
Formatting fixes here too. See examples above for proper formatting.
Since you're relatively new to GCC development, please make the changes
noted above and resubmit this patch.
jeff
