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.
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
