Hi!
As the second testcase shows, we shouldn't be calling convert_for_*
with TREE_TYPE (decl) for bitfields, we need DECL_BIT_FIELD_TYPE
in that case instead (unlowered_expr_type doesn't work here,
as that wants a COMPONENT_REF which we don't have).
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2019-11-29 Jakub Jelinek <ja...@redhat.com>
PR c++/92732
* typeck2.c (digest_nsdmi_init): For bitfields, use
DECL_BIT_FIELD_TYPE instead of TREE_TYPE.
* g++.dg/cpp2a/bitfield3.C: Don't expect narrowing conversion
warnings.
* g++.dg/cpp2a/bitfield4.C: New test.
--- gcc/cp/typeck2.c.jj 2019-11-25 22:44:24.911346688 +0100
+++ gcc/cp/typeck2.c 2019-11-29 21:48:58.825713516 +0100
@@ -1335,6 +1335,9 @@ digest_nsdmi_init (tree decl, tree init,
gcc_assert (TREE_CODE (decl) == FIELD_DECL);
tree type = TREE_TYPE (decl);
+ if (DECL_BIT_FIELD_TYPE (decl))
+ type = cp_build_qualified_type (DECL_BIT_FIELD_TYPE (decl),
+ cp_type_quals (type));
int flags = LOOKUP_IMPLICIT;
if (DIRECT_LIST_INIT_P (init))
{
--- gcc/testsuite/g++.dg/cpp2a/bitfield3.C.jj 2017-09-29 19:49:17.684827064
+0200
+++ gcc/testsuite/g++.dg/cpp2a/bitfield3.C 2019-11-29 21:52:56.636122855
+0100
@@ -15,11 +15,9 @@ const int b = 0;
struct S {
int c : 5 = 2 * a; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
int d : 6 { c + a }; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
- // { dg-warning "narrowing conversion
of" "" { target *-*-* } .-1 }
int e : true ? 7 : a = 3;
int f : (true ? 8 : b) = d + a; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
int g : (true ? 9 : b) { f + a }; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
- // { dg-warning "narrowing conversion
of" "" { target *-*-* } .-1 }
int h : 1 || new int { 0 };
int i = g + a;
};
@@ -28,11 +26,9 @@ template <bool V, int W>
struct U {
int j : W = 3 * a; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
int k : W { j + a }; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
- // { dg-warning "narrowing conversion
of" "" { target *-*-* } .-1 }
int l : V ? 7 : a = 3;
int m : (V ? W : b) = k + a; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
int n : (V ? W : b) { m + a }; // { dg-warning "default member
initializers for bit-fields only available with" "" { target c++17_down } }
- // { dg-warning "narrowing conversion
of" "" { target *-*-* } .-1 }
int o : 1 || new int { 0 };
int p = n + a;
};
--- gcc/testsuite/g++.dg/cpp2a/bitfield4.C.jj 2019-11-29 21:48:28.752167687
+0100
+++ gcc/testsuite/g++.dg/cpp2a/bitfield4.C 2019-11-29 21:52:40.548365714
+0100
@@ -0,0 +1,12 @@
+// PR c++/92732
+// { dg-do compile { target c++17 } }
+// { dg-options "" }
+
+enum class byte : unsigned char { };
+using uint8_t = unsigned char;
+
+struct T
+{
+ byte a : 2 = byte{0}; // { dg-warning "default member initializers
for bit-fields only available with" "" { target c++17_down } }
+ uint8_t b : 2 = 0; // { dg-warning "default member initializers for
bit-fields only available with" "" { target c++17_down } }
+} t;
Jakub
