Hi again,
I managed to spend much more time on the issue and I'm starting a new
thread with a mature - IMHO - proposal: the big thing is the use of the
existing check_array_designated_initializer in
process_init_constructor_array, which calls maybe_constant_value, as we
want, and covers all the ill-formed cases which I can imagine. I'm also
tweaking a bit the parser to check the return value of
require_potential_rvalue_constant_expression in order to avoid redundant
diagnostic in some cases. Also, a couple more testcases beyond the bug
report.
Tested x86_64-linux.
Thanks, Paolo.
////////////////////////
/cp
2017-11-17 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/82593
* decl.c (check_array_designated_initializer): Not static.
* cp-tree.h (check_array_designated_initializer): Declare.
* typeck2.c (process_init_constructor_array): Call the latter.
* parser.c (cp_parser_initializer_list): Check the return value
of require_potential_rvalue_constant_expression.
/testsuite
2017-11-17 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/82593
* g++.dg/cpp0x/desig2.C: New.
* g++.dg/cpp0x/desig3.C: Likewise.
* g++.dg/cpp0x/desig4.C: Likewise.
Index: cp/cp-tree.h
===================================================================
--- cp/cp-tree.h (revision 254858)
+++ cp/cp-tree.h (working copy)
@@ -6190,6 +6190,8 @@ extern bool require_deduced_type (tree, tsubst_fl
extern tree finish_case_label (location_t, tree, tree);
extern tree cxx_maybe_build_cleanup (tree, tsubst_flags_t);
+extern bool check_array_designated_initializer (constructor_elt *,
+ unsigned HOST_WIDE_INT);
/* in decl2.c */
extern void record_mangling (tree, bool);
Index: cp/decl.c
===================================================================
--- cp/decl.c (revision 254858)
+++ cp/decl.c (working copy)
@@ -5245,7 +5245,7 @@ grok_reference_init (tree decl, tree type, tree in
initializer. If it does, an error is issued. Returns true if CE
is valid, i.e., does not have a designated initializer. */
-static bool
+bool
check_array_designated_initializer (constructor_elt *ce,
unsigned HOST_WIDE_INT index)
{
Index: cp/parser.c
===================================================================
--- cp/parser.c (revision 254858)
+++ cp/parser.c (working copy)
@@ -22193,8 +22193,10 @@ cp_parser_initializer_list (cp_parser* parser, boo
if (!cp_parser_parse_definitely (parser))
designator = NULL_TREE;
- else if (non_const)
- require_potential_rvalue_constant_expression (designator);
+ else if (non_const
+ && (!require_potential_rvalue_constant_expression
+ (designator)))
+ designator = NULL_TREE;
}
else
designator = NULL_TREE;
Index: cp/typeck2.c
===================================================================
--- cp/typeck2.c (revision 254858)
+++ cp/typeck2.c (working copy)
@@ -1289,17 +1289,8 @@ process_init_constructor_array (tree type, tree in
FOR_EACH_VEC_SAFE_ELT (v, i, ce)
{
- if (ce->index)
- {
- gcc_assert (TREE_CODE (ce->index) == INTEGER_CST);
- if (compare_tree_int (ce->index, i) != 0)
- {
- ce->value = error_mark_node;
- sorry ("non-trivial designated initializers not supported");
- }
- }
- else
- ce->index = size_int (i);
+ ce->index = (check_array_designated_initializer (ce, i)
+ ? size_int (i) : error_mark_node);
gcc_assert (ce->value);
ce->value = massage_init_elt (TREE_TYPE (type), ce->value, complain);
Index: testsuite/g++.dg/cpp0x/desig2.C
===================================================================
--- testsuite/g++.dg/cpp0x/desig2.C (nonexistent)
+++ testsuite/g++.dg/cpp0x/desig2.C (working copy)
@@ -0,0 +1,23 @@
+// PR c++/82593
+// { dg-do compile { target c++11 } }
+// { dg-options "" }
+
+enum {
+ INDEX1 = 0,
+ INDEX2
+};
+
+class SomeClass {
+public:
+ SomeClass();
+private:
+ struct { int field; } member[2];
+};
+
+SomeClass::SomeClass()
+ : member({
+ [INDEX1] = { .field = 0 },
+ [INDEX2] = { .field = 1 }
+ })
+{
+}
Index: testsuite/g++.dg/cpp0x/desig3.C
===================================================================
--- testsuite/g++.dg/cpp0x/desig3.C (nonexistent)
+++ testsuite/g++.dg/cpp0x/desig3.C (working copy)
@@ -0,0 +1,21 @@
+// PR c++/82593
+// { dg-do compile { target c++11 } }
+// { dg-options "" }
+
+const int INDEX1 = 0;
+const int INDEX2 = 1;
+
+class SomeClass {
+public:
+ SomeClass();
+private:
+ struct { int field; } member[2];
+};
+
+SomeClass::SomeClass()
+ : member({
+ [INDEX1] = { .field = 0 },
+ [INDEX2] = { .field = 1 }
+ })
+{
+}
Index: testsuite/g++.dg/cpp0x/desig4.C
===================================================================
--- testsuite/g++.dg/cpp0x/desig4.C (nonexistent)
+++ testsuite/g++.dg/cpp0x/desig4.C (working copy)
@@ -0,0 +1,21 @@
+// PR c++/82593
+// { dg-do compile { target c++11 } }
+// { dg-options "" }
+
+int INDEX1 = 0;
+int INDEX2 = 1;
+
+class SomeClass {
+public:
+ SomeClass();
+private:
+ struct { int field; } member[2];
+};
+
+SomeClass::SomeClass()
+ : member({
+ [INDEX1] = { .field = 0 }, // { dg-error "constant expression" }
+ [INDEX2] = { .field = 1 } // { dg-error "constant expression" }
+ })
+{
+}
