Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? I don't
claim that this has to go to 14 though.
-- >8 --
...from another array in a mem-initializer should not be accepted.
We already reject
struct string {} a[1];
string x[1](a);
but
struct pair {
string s[1];
pair() : s(a) {}
};
is wrongly accepted.
It started to be accepted with r0-110915-ga034826198b771:
<https://gcc.gnu.org/pipermail/gcc-patches/2011-August/320236.html>
which was supposed to be a cleanup, not a deliberate change to start
accepting the code. The build_vec_init_expr code was added in r165976:
<https://gcc.gnu.org/pipermail/gcc-patches/2010-October/297582.html>.
It appears that we do the magic copy array when we have a defaulted
constructor and we generate code for its mem-initializer which
initializes an array. I also see that we go that path for compound
literals. So when initializing an array member, we can limit building
up a VEC_INIT_EXPR to those special cases.
PR c++/59465
gcc/cp/ChangeLog:
* init.cc (can_init_array_with_p): New.
(perform_member_init): Check it.
gcc/testsuite/ChangeLog:
* g++.dg/init/array62.C: New test.
* g++.dg/init/array63.C: New test.
* g++.dg/init/array64.C: New test.
---
gcc/cp/init.cc | 27 ++++++++++++++++++++++++++-
gcc/testsuite/g++.dg/init/array62.C | 19 +++++++++++++++++++
gcc/testsuite/g++.dg/init/array63.C | 13 +++++++++++++
gcc/testsuite/g++.dg/init/array64.C | 22 ++++++++++++++++++++++
4 files changed, 80 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/init/array62.C
create mode 100644 gcc/testsuite/g++.dg/init/array63.C
create mode 100644 gcc/testsuite/g++.dg/init/array64.C
diff --git a/gcc/cp/init.cc b/gcc/cp/init.cc
index d2586fad86b..fb8c0e521fb 100644
--- a/gcc/cp/init.cc
+++ b/gcc/cp/init.cc
@@ -934,6 +934,31 @@ find_uninit_fields (tree *t, hash_set<tree>
*uninitialized, tree member)
}
}
+/* Return true if it's OK to initialize an array from INIT. Mere mortals
+ can't copy arrays, but the compiler can do so with a VEC_INIT_EXPR in
+ certain cases. */
+
+static bool
+can_init_array_with_p (tree init)
+{
+ if (!init)
+ return true;
+
+ /* We're called from synthesize_method, and we're processing the
+ mem-initializers of a constructor. */
+ if (DECL_DEFAULTED_FN (current_function_decl))
+ return true;
+ /* As an extension, we allow copying from a compound literal. */
+ else if (TREE_CODE (init) == TARGET_EXPR)
+ {
+ init = TARGET_EXPR_INITIAL (init);
+ if (TREE_CODE (init) == CONSTRUCTOR)
+ return CONSTRUCTOR_C99_COMPOUND_LITERAL (init);
+ }
+
+ return false;
+}
+
/* Initialize MEMBER, a FIELD_DECL, with INIT, a TREE_LIST of
arguments. If TREE_LIST is void_type_node, an empty initializer
list was given; if NULL_TREE no initializer was given. UNINITIALIZED
@@ -1085,7 +1110,7 @@ perform_member_init (tree member, tree init,
hash_set<tree> &uninitialized)
else if (type_build_ctor_call (type)
|| (init && CLASS_TYPE_P (strip_array_types (type))))
{
- if (TREE_CODE (type) == ARRAY_TYPE)
+ if (TREE_CODE (type) == ARRAY_TYPE && can_init_array_with_p (init))
{
if (init == NULL_TREE
|| same_type_ignoring_top_level_qualifiers_p (type,
diff --git a/gcc/testsuite/g++.dg/init/array62.C
b/gcc/testsuite/g++.dg/init/array62.C
new file mode 100644
index 00000000000..6d3935d7a66
--- /dev/null
+++ b/gcc/testsuite/g++.dg/init/array62.C
@@ -0,0 +1,19 @@
+// PR c++/59465
+// { dg-do compile }
+
+struct string {} a[1];
+struct pair {
+ string s[1];
+ pair() : s(a) {} // { dg-error "array must be initialized" }
+};
+
+struct S {
+ char s[10];
+ S() : s("aaa") {}
+};
+
+void
+g ()
+{
+ string x[1](a); // { dg-error "array must be initialized" }
+}
diff --git a/gcc/testsuite/g++.dg/init/array63.C
b/gcc/testsuite/g++.dg/init/array63.C
new file mode 100644
index 00000000000..96bc9a64b26
--- /dev/null
+++ b/gcc/testsuite/g++.dg/init/array63.C
@@ -0,0 +1,13 @@
+// PR c++/59465
+// { dg-do compile }
+
+struct I {
+ const bool b;
+};
+struct O {
+ I a[2];
+ static I const data[2];
+ O() : a(data){} // { dg-error "array must be initialized" }
+};
+
+I const O::data[2] = {true, false};
diff --git a/gcc/testsuite/g++.dg/init/array64.C
b/gcc/testsuite/g++.dg/init/array64.C
new file mode 100644
index 00000000000..bbdd70c6df8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/init/array64.C
@@ -0,0 +1,22 @@
+// PR c++/59465
+// { dg-do compile }
+
+static const int my_size = 10;
+
+class UserType
+{
+public:
+ UserType(): f_(){}
+private:
+int f_;
+};
+
+typedef UserType Array[my_size];
+
+class Foo
+{
+public:
+ Foo(Array& m) : m_(m) {}; // { dg-error "array must be initialized" }
+private:
+ Array m_;
+};
base-commit: 574fd1f17f100c7c355ad26bc525ab5a3386bb2d
--
2.44.0
