Hi!
{,u8}display_string_of was printing any unnamed FIELD_DECL as
%T::<unnamed bit-field>, but anon union member is also unnamed and
is not a bit-field.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
trunk?
2026-03-07 Jakub Jelinek <[email protected]>
PR c++/124388
* reflect.cc (eval_display_string_of): Only print <unnmamed bit-field>
for DECL_UNNAMED_BIT_FIELD, otherwise print <unnamed member>.
* g++.dg/reflect/display_string_of1.C (S, NS5::S): Add
union { int a; }. Add static_assertions that the unnamed non-static
data member is printed as <unnamed member>.
* g++.dg/reflect/u8display_string_of1.C (S, NS5::S): Add
union { int a; }. Add static_assertions that the unnamed non-static
data member is printed as <unnamed member>.
--- gcc/cp/reflect.cc.jj 2026-03-05 09:19:22.173774816 +0100
+++ gcc/cp/reflect.cc 2026-03-06 11:52:58.021949635 +0100
@@ -3604,7 +3604,12 @@ eval_display_string_of (location_t loc,
else if (DECL_P (r) && (DECL_NAME (r) || TREE_CODE (r) == NAMESPACE_DECL))
pp_printf (&pp, "%D", r);
else if (TREE_CODE (r) == FIELD_DECL)
- pp_printf (&pp, "%T::<unnamed bit-field>", DECL_CONTEXT (r));
+ {
+ if (DECL_UNNAMED_BIT_FIELD (r))
+ pp_printf (&pp, "%T::<unnamed bit-field>", DECL_CONTEXT (r));
+ else
+ pp_printf (&pp, "%T::<unnamed member>", DECL_CONTEXT (r));
+ }
else if (kind == REFLECT_BASE)
{
tree d = direct_base_derived (r);
--- gcc/testsuite/g++.dg/reflect/display_string_of1.C.jj 2026-01-15
16:33:47.007097959 +0100
+++ gcc/testsuite/g++.dg/reflect/display_string_of1.C 2026-03-06
11:51:46.572128144 +0100
@@ -17,6 +17,7 @@ struct B {};
struct S : B {
int mem;
int : 0;
+ union { int a; };
};
struct T {
T () {}
@@ -106,6 +107,7 @@ foo (int a, const long b, T c, int d[4],
static_assert (display_string_of (^^S) == "S");
static_assert (display_string_of (^^S::mem) == "S::mem");
static_assert (display_string_of (members_of (^^S, ctx)[1]) == "S::<unnamed
bit-field>");
+ static_assert (display_string_of (nonstatic_data_members_of (^^S, ctx)[1])
== "S::<unnamed member>");
static_assert (display_string_of (^^TCls) == "template<auto <anonymous> >
struct TCls");
static_assert (display_string_of (^^TFn) == "template<auto <anonymous> >
void TFn()");
static_assert (display_string_of (^^TVar) == "template<auto <anonymous> >
int TVar<<anonymous> >");
@@ -145,6 +147,7 @@ namespace NS5 {
struct S : B {
int mem;
int : 0;
+ union { int a; };
};
struct T {
T () {}
@@ -212,6 +215,7 @@ namespace NS5 {
static_assert (display_string_of (^^S) == "NS5::S");
static_assert (display_string_of (^^S::mem) == "NS5::S::mem");
static_assert (display_string_of (members_of (^^S, ctx)[1]) ==
"NS5::S::<unnamed bit-field>");
+ static_assert (display_string_of (nonstatic_data_members_of (^^S, ctx)[1])
== "NS5::S::<unnamed member>");
static_assert (display_string_of (^^TCls) == "template<auto <anonymous> >
struct NS5::TCls");
static_assert (display_string_of (^^TFn) == "template<auto <anonymous> >
void NS5::TFn()");
static_assert (display_string_of (^^TVar) == "template<auto <anonymous> >
int NS5::TVar<<anonymous> >");
--- gcc/testsuite/g++.dg/reflect/u8display_string_of1.C.jj 2026-01-15
16:33:47.017097789 +0100
+++ gcc/testsuite/g++.dg/reflect/u8display_string_of1.C 2026-03-06
11:37:31.895312350 +0100
@@ -17,6 +17,7 @@ struct B {};
struct S : B {
int mem;
int : 0;
+ union { int a; };
};
struct T {
T () {}
@@ -106,6 +107,7 @@ foo (int a, const long b, T c, int d[4],
static_assert (u8display_string_of (^^S) == u8"S");
static_assert (u8display_string_of (^^S::mem) == u8"S::mem");
static_assert (u8display_string_of (members_of (^^S, ctx)[1]) ==
u8"S::<unnamed bit-field>");
+ static_assert (u8display_string_of (nonstatic_data_members_of (^^S, ctx)[1])
== u8"S::<unnamed member>");
static_assert (u8display_string_of (^^TCls) == u8"template<auto <anonymous>
> struct TCls");
static_assert (u8display_string_of (^^TFn) == u8"template<auto <anonymous> >
void TFn()");
static_assert (u8display_string_of (^^TVar) == u8"template<auto <anonymous>
> int TVar<<anonymous> >");
@@ -145,6 +147,7 @@ namespace NS5 {
struct S : B {
int mem;
int : 0;
+ union { int a; };
};
struct T {
T () {}
@@ -212,6 +215,7 @@ namespace NS5 {
static_assert (u8display_string_of (^^S) == u8"NS5::S");
static_assert (u8display_string_of (^^S::mem) == u8"NS5::S::mem");
static_assert (u8display_string_of (members_of (^^S, ctx)[1]) ==
u8"NS5::S::<unnamed bit-field>");
+ static_assert (u8display_string_of (nonstatic_data_members_of (^^S,
ctx)[1]) == u8"NS5::S::<unnamed member>");
static_assert (u8display_string_of (^^TCls) == u8"template<auto
<anonymous> > struct NS5::TCls");
static_assert (u8display_string_of (^^TFn) == u8"template<auto <anonymous>
> void NS5::TFn()");
static_assert (u8display_string_of (^^TVar) == u8"template<auto
<anonymous> > int NS5::TVar<<anonymous> >");
Jakub
