On 8/7/26 8:45 AM, Jakub Jelinek wrote:
Hi!
We ICE when trying to mangle the TEMPLATE_DECL of a conversion operator,
because FNDECL_USED_AUTO macro requires FUNCTION_DECL, but here we
have a TEMPLATE_DECL instead.
In this case, DECL_CONV_FN_TYPE contains the right type, so this patch
just guards the FNDECL_USED_AUTO macro use on FUNCTION_DECLs.
Hmm, if it's valid to get a TEMPLATE_DECL here I think we want to
STRIP_TEMPLATE earlier in the function to avoid the need for this; lots
of other things here seem to assume we're looking at the inner decl.
So far tested on
GXX_TESTSUITE_STDS=98,11,14,17,20,23,26,29 make check-g++ -j32 -k
RUNTESTFLAGS="dg.exp='reflect/*'"
Ok for trunk if it passes full bootstrap/regtest?
2026-08-07 Jakub Jelinek <[email protected]>
PR c++/126093
* mangle.cc (write_unqualified_name): Only check FNDECL_USED_AUTO
on FUNCTION_DECLs.
* g++.dg/reflect/mangle1.C: Add 2 new tests for reflections of
conversion templates.
--- gcc/cp/mangle.cc.jj 2026-08-06 13:24:02.000000000 +0200
+++ gcc/cp/mangle.cc 2026-08-07 14:06:15.092252321 +0200
@@ -1567,7 +1567,8 @@ write_unqualified_name (tree decl)
fn_type = get_mostly_instantiated_function_type (decl);
type = TREE_TYPE (fn_type);
}
- else if (FNDECL_USED_AUTO (decl))
+ else if (TREE_CODE (decl) == FUNCTION_DECL
+ && FNDECL_USED_AUTO (decl))
type = DECL_SAVED_AUTO_RETURN_TYPE (decl);
else
type = DECL_CONV_FN_TYPE (decl);
--- gcc/testsuite/g++.dg/reflect/mangle1.C.jj 2026-08-06 13:24:02.480925614
+0200
+++ gcc/testsuite/g++.dg/reflect/mangle1.C 2026-08-07 14:30:30.275043881
+0200
@@ -15,6 +15,10 @@ struct S : B {
int : 0;
static int var;
};
+struct Q {
+ template <typename T>
+ operator T () { return T (); }
+};
struct W { union {}; union {}; union {}; union {}; };
template <auto> struct TCls {};
template <auto> void TFn ();
@@ -65,6 +69,10 @@ namespace NS2 {
struct Z {
};
struct AA { int a, b; };
+ struct Q {
+ template <int N>
+ operator int () { return N; }
+ };
}
constexpr auto ctx = std::meta::access_context::current ();
@@ -147,6 +155,8 @@ baz (int x)
bar <241, ^^NS2::TCls> (); // class template
bar <250, ^^TFn> (); // function template
bar <251, ^^NS2::TFn> (); // function template
+ bar <252, members_of (^^Q, ctx)[0]> (); // function template
+ bar <253, members_of (^^NS2::Q, ctx)[0]> (); // function template
bar <260, ^^TVar> (); // variable template
bar <261, ^^NS2::TVar> (); // variable template
bar <270, ^^TAlias> (); // alias template
@@ -239,6 +249,8 @@ baz (int x)
// { dg-final { scan-assembler "_Z3barILi241ELDmct3NS24TClsEEvv" } }
// { dg-final { scan-assembler "_Z3barILi250ELDmft3TFnEEvv" } }
// { dg-final { scan-assembler "_Z3barILi251ELDmft3NS23TFnEEvv" } }
+// { dg-final { scan-assembler "_Z3barILi252ELDmft1QcvT_EEvv" } }
+// { dg-final { scan-assembler "_Z3barILi253ELDmft3NS21QcviEEvv" } }
// { dg-final { scan-assembler "_Z3barILi260ELDmvt4TVarEEvv" } }
// { dg-final { scan-assembler "_Z3barILi261ELDmvt3NS24TVarEEvv" } }
// { dg-final { scan-assembler "_Z3barILi270ELDmat6TAliasEEvv" } }
Jakub
