Hi,
On 06/04/2014 04:16 PM, Jason Merrill wrote:
if (TREE_CODE (init) == TREE_LIST
- && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
+ && TREE_CODE (type) == ARRAY_TYPE
+ /* C++11 8.5/17: "If the destination type is an array of
characters,
+ an array of char16_t, an array of char32_t, or an array of
wchar_t,
+ and the initializer is a string literal...". */
+ && !(char_type_p (TREE_TYPE (TYPE_MAIN_VARIANT (type)))
+ && TREE_CODE (TREE_VALUE (init)) == STRING_CST))
{
error ("cannot initialize arrays using this syntax");
return NULL_TREE;
Can we just remove this error rather than add a condition? I think
it's covered in other places.
Removing it certainly passes testing.
The patch doesn't seem to fix
char s[] ("foo");
which I think also ought to be well-formed.
Right. Thus I reworked a bit the code in cp_complete_array_type to
handle specially a single-element TREE_LIST together a single-element
CONSTRUCTOR. Tested x86_64-linux.
Thanks!
Paolo.
//////////////////
/cp
2014-06-04 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/43453
* typeck.c (cp_build_modify_expr): Handle array of characters
initialized by a string literal.
* typeck2.c (store_init_value): Remove redundant check.
* decl.c (cp_complete_array_type): Rework code handling initialization
from a string literal to handle single element TREE_LIST too.
/testsuite
2014-06-04 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/43453
* g++.dg/init/pr43453.C: New.
Index: cp/decl.c
===================================================================
--- cp/decl.c (revision 211225)
+++ cp/decl.c (working copy)
@@ -7176,20 +7176,21 @@ cp_complete_array_type (tree *ptype, tree initial_
tree value;
/* An array of character type can be initialized from a
- brace-enclosed string constant.
-
- FIXME: this code is duplicated from reshape_init. Probably
- we should just call reshape_init here? */
- if (char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (*ptype)))
- && TREE_CODE (initial_value) == CONSTRUCTOR
- && !vec_safe_is_empty (CONSTRUCTOR_ELTS (initial_value)))
+ brace-enclosed string constant. */
+ if (char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (*ptype))))
{
- vec<constructor_elt, va_gc> *v = CONSTRUCTOR_ELTS (initial_value);
- tree value = (*v)[0].value;
+ tree svalue = NULL_TREE;
- if (TREE_CODE (value) == STRING_CST
- && v->length () == 1)
- initial_value = value;
+ if (TREE_CODE (initial_value) == CONSTRUCTOR
+ && vec_safe_length (CONSTRUCTOR_ELTS (initial_value)) == 1)
+ svalue = (*CONSTRUCTOR_ELTS (initial_value))[0].value;
+ else if (TREE_CODE (initial_value) == TREE_LIST
+ && list_length (initial_value) == 1)
+ /* We get here with code like `char s[] ("abc");' */
+ svalue = TREE_VALUE (initial_value);
+
+ if (svalue && TREE_CODE (svalue) == STRING_CST)
+ initial_value = svalue;
}
/* If any of the elements are parameter packs, we can't actually
Index: cp/typeck.c
===================================================================
--- cp/typeck.c (revision 211225)
+++ cp/typeck.c (working copy)
@@ -7511,6 +7511,18 @@ cp_build_modify_expr (tree lhs, enum tree_code mod
return error_mark_node;
}
+ /* C++11 8.5/17: "If the destination type is an array of characters,
+ an array of char16_t, an array of char32_t, or an array of wchar_t,
+ and the initializer is a string literal...". */
+ else if (TREE_CODE (newrhs) == STRING_CST
+ && char_type_p (TREE_TYPE (TYPE_MAIN_VARIANT (lhstype)))
+ && modifycode == INIT_EXPR)
+ {
+ newrhs = digest_init (lhstype, newrhs, complain);
+ if (newrhs == error_mark_node)
+ return error_mark_node;
+ }
+
else if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
TYPE_MAIN_VARIANT (TREE_TYPE (newrhs))))
{
Index: cp/typeck2.c
===================================================================
--- cp/typeck2.c (revision 211225)
+++ cp/typeck2.c (working copy)
@@ -785,16 +785,9 @@ store_init_value (tree decl, tree init, vec<tree,
{
gcc_assert (TREE_CODE (decl) != RESULT_DECL);
- if (TREE_CODE (init) == TREE_LIST
- && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
- {
- error ("cannot initialize arrays using this syntax");
- return NULL_TREE;
- }
- else
- /* We get here with code like `int a (2);' */
- init = build_x_compound_expr_from_list (init, ELK_INIT,
- tf_warning_or_error);
+ /* We get here with code like `int a (2);' */
+ init = build_x_compound_expr_from_list (init, ELK_INIT,
+ tf_warning_or_error);
}
/* End of special C++ code. */
Index: testsuite/g++.dg/init/pr43453.C
===================================================================
--- testsuite/g++.dg/init/pr43453.C (revision 0)
+++ testsuite/g++.dg/init/pr43453.C (working copy)
@@ -0,0 +1,33 @@
+// PR c++/43453
+
+struct A {
+ char x[4];
+ A() : x("bug") { };
+};
+
+char x [4] ("bug");
+
+struct CA {
+ const char cx[4];
+ CA() : cx("bug") { };
+};
+
+const char cx [4] ("bug");
+
+struct B {
+ char y[4];
+ B() : y("bu") { };
+};
+
+char y [4] ("bu");
+
+struct C {
+ char z[4];
+ C() : z("bugs") { }; // { dg-error "too long" }
+};
+
+char z [4] ("bugs"); // { dg-error "too long" }
+
+char k [] ("bug");
+
+const char ck [] ("bug");
