Our C++20 designated initializer handling was broken with members of class
type; we would find the relevant member and then try to find a member of
the member with the same name. Or we would sometimes ignore the designator
entirely. The former problem is fixed by the change to reshape_init_class,
the latter by the change to reshape_init_r.
Tested x86_64-pc-linux-gnu, applying to trunk.
PR c++/103337
PR c++/102740
PR c++/103299
PR c++/102538
gcc/cp/ChangeLog:
* decl.cc (reshape_init_class): Avoid looking for designator
after we found it.
(reshape_init_r): Keep looking for designator.
gcc/testsuite/ChangeLog:
* g++.dg/ext/flexary3.C: Remove one error.
* g++.dg/parse/pr43765.C: Likewise.
* g++.dg/cpp2a/desig22.C: New test.
* g++.dg/cpp2a/desig23.C: New test.
* g++.dg/cpp2a/desig24.C: New test.
* g++.dg/cpp2a/desig25.C: New test.
---
gcc/cp/decl.cc | 47 +++++++++++++++++++++++++---
gcc/testsuite/g++.dg/cpp2a/desig22.C | 11 +++++++
gcc/testsuite/g++.dg/cpp2a/desig23.C | 20 ++++++++++++
gcc/testsuite/g++.dg/cpp2a/desig24.C | 11 +++++++
gcc/testsuite/g++.dg/cpp2a/desig25.C | 13 ++++++++
gcc/testsuite/g++.dg/ext/flexary3.C | 2 +-
gcc/testsuite/g++.dg/parse/pr43765.C | 6 ++--
7 files changed, 101 insertions(+), 9 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp2a/desig22.C
create mode 100644 gcc/testsuite/g++.dg/cpp2a/desig23.C
create mode 100644 gcc/testsuite/g++.dg/cpp2a/desig24.C
create mode 100644 gcc/testsuite/g++.dg/cpp2a/desig25.C
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 375385e0013..34d9dad9fb0 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -6598,8 +6598,9 @@ reshape_init_class (tree type, reshape_iter *d, bool
first_initializer_p,
{
tree field_init;
constructor_elt *old_cur = d->cur;
+ bool direct_desig = false;
- /* Handle designated initializers, as an extension. */
+ /* Handle C++20 designated initializers. */
if (d->cur->index)
{
if (d->cur->index == error_mark_node)
@@ -6617,7 +6618,10 @@ reshape_init_class (tree type, reshape_iter *d, bool
first_initializer_p,
}
}
else if (TREE_CODE (d->cur->index) == IDENTIFIER_NODE)
- field = get_class_binding (type, d->cur->index);
+ {
+ field = get_class_binding (type, d->cur->index);
+ direct_desig = true;
+ }
else
{
if (complain & tf_error)
@@ -6669,6 +6673,7 @@ reshape_init_class (tree type, reshape_iter *d, bool
first_initializer_p,
break;
gcc_assert (aafield);
field = aafield;
+ direct_desig = false;
}
}
@@ -6683,9 +6688,32 @@ reshape_init_class (tree type, reshape_iter *d, bool
first_initializer_p,
assumed to correspond to no elements of the initializer list. */
goto continue_;
- field_init = reshape_init_r (TREE_TYPE (field), d,
- /*first_initializer_p=*/NULL_TREE,
- complain);
+ if (direct_desig)
+ {
+ /* The designated field F is initialized from this one element:
+ Temporarily clear the designator so a recursive reshape_init_class
+ doesn't try to find it again in F, and adjust d->end so we don't
+ try to use the next initializer to initialize another member of F.
+
+ Note that we don't want these changes if we found the designator
+ inside an anon aggr above; we leave them alone to implement:
+
+ "If the element is an anonymous union member and the initializer
+ list is a brace-enclosed designated- initializer-list, the element
+ is initialized by the designated-initializer-list { D }, where D
+ is the designated- initializer-clause naming a member of the
+ anonymous union member." */
+ auto end_ = make_temp_override (d->end, d->cur + 1);
+ auto idx_ = make_temp_override (d->cur->index, NULL_TREE);
+ field_init = reshape_init_r (TREE_TYPE (field), d,
+ /*first_initializer_p=*/NULL_TREE,
+ complain);
+ }
+ else
+ field_init = reshape_init_r (TREE_TYPE (field), d,
+ /*first_initializer_p=*/NULL_TREE,
+ complain);
+
if (field_init == error_mark_node)
return error_mark_node;
@@ -6941,6 +6969,15 @@ reshape_init_r (tree type, reshape_iter *d, tree
first_initializer_p,
to handle initialization of arrays and similar. */
else if (COMPOUND_LITERAL_P (stripped_init))
gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (stripped_init));
+ /* If we have an unresolved designator, we need to find the member it
+ designates within TYPE, so proceed to the routines below. For
+ FIELD_DECL or INTEGER_CST designators, we're already initializing
+ the designated element. */
+ else if (d->cur->index
+ && TREE_CODE (d->cur->index) == IDENTIFIER_NODE)
+ /* Brace elision with designators is only permitted for anonymous
+ aggregates. */
+ gcc_checking_assert (ANON_AGGR_TYPE_P (type));
/* A CONSTRUCTOR of the target's type is a previously
digested initializer. */
else if (same_type_ignoring_top_level_qualifiers_p (type, init_type))
diff --git a/gcc/testsuite/g++.dg/cpp2a/desig22.C
b/gcc/testsuite/g++.dg/cpp2a/desig22.C
new file mode 100644
index 00000000000..ba083f8e3d5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/desig22.C
@@ -0,0 +1,11 @@
+// PR c++/103337
+// { dg-do compile { target c++20 } }
+
+struct op_t {
+ struct put_t {
+ int x;
+ } put;
+};
+
+op_t x{0}; // OK
+op_t y{.put=0}; // bogus error: 'op_t::put_t' has no non-static data member
named 'put'
diff --git a/gcc/testsuite/g++.dg/cpp2a/desig23.C
b/gcc/testsuite/g++.dg/cpp2a/desig23.C
new file mode 100644
index 00000000000..4354e644f6a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/desig23.C
@@ -0,0 +1,20 @@
+// PR c++/102740
+// { dg-do compile { target c++20 } }
+// { dg-additional-options -Wmissing-braces }
+
+typedef struct {
+ union {
+ struct {
+ const void* content;
+ } put;
+ };
+} op_t;
+
+op_t f(const char* alias) {
+ return op_t{
+ .put =
+ {
+ .content = alias,
+ },
+ }; // { dg-warning "missing braces" }
+}
diff --git a/gcc/testsuite/g++.dg/cpp2a/desig24.C
b/gcc/testsuite/g++.dg/cpp2a/desig24.C
new file mode 100644
index 00000000000..219cc9c3b8e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/desig24.C
@@ -0,0 +1,11 @@
+// PR c++/103299
+// { dg-do compile { target c++20 } }
+
+struct foo {
+ union {
+ int fp1{};
+ char fp2;
+ };
+};
+
+static_assert(foo{.fp2={}}.fp2 == 0);
diff --git a/gcc/testsuite/g++.dg/cpp2a/desig25.C
b/gcc/testsuite/g++.dg/cpp2a/desig25.C
new file mode 100644
index 00000000000..9da958c29e9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/desig25.C
@@ -0,0 +1,13 @@
+// PR c++/102538
+// { dg-do run { target c++20 } }
+
+struct X { union { char r8[8]; int r32[2]; }; };
+struct Y { X v[1]; };
+Y x = { { { .r32 = { 5, 6 } } } };
+
+int
+main ()
+{
+ if (x.v[0].r32[0] != 5 || x.v[0].r32[1] != 6)
+ __builtin_abort ();
+}
diff --git a/gcc/testsuite/g++.dg/ext/flexary3.C
b/gcc/testsuite/g++.dg/ext/flexary3.C
index 34b17254f8c..8344b42dd16 100644
--- a/gcc/testsuite/g++.dg/ext/flexary3.C
+++ b/gcc/testsuite/g++.dg/ext/flexary3.C
@@ -16,7 +16,7 @@ struct s {
int main()
{
- struct s s = { .c = 0 }; // { dg-error "initializer" }
+ struct s s = { .c = 0 };
// { dg-error "non-static initialization of a flexible array member" "" {
target *-*-* } .-1 }
return 0;
}
diff --git a/gcc/testsuite/g++.dg/parse/pr43765.C
b/gcc/testsuite/g++.dg/parse/pr43765.C
index 5e602204007..aa099a4d20b 100644
--- a/gcc/testsuite/g++.dg/parse/pr43765.C
+++ b/gcc/testsuite/g++.dg/parse/pr43765.C
@@ -12,6 +12,6 @@ SomeType vals[] =
{
{ 0, values : temp, }, // { dg-error "either all initializer clauses
should be designated or none of them should be" "" { target c++2a } }
0
- }; // { dg-error "GNU-style designated initializer for an array|cannot
convert" }
-// (note the error above is on the wrong line)
- // { dg-error "initialization of flexible array member in a nested
context" "" { target *-*-* } .-2 }
+ };
+// (note the error below is on the wrong line)
+// { dg-error "initialization of flexible array member in a nested context" ""
{ target *-*-* } .-2 }
base-commit: 70b8f43695b0e6fabc760d247ac83f354092b21d
prerequisite-patch-id: d89344aafac30ce0b8645945beb2d94b7ddb3515
--
2.27.0
