The FUNCTION_DECL we build for __dynamic_cast has an empty DECL_CONTEXT, but trees_out::tree_node expects all FUNCTION_DECLs to have non-empty DECL_CONTEXT thus we crash when streaming out the dynamic_cast in the below testcase.
This patch naively fixes this by setting DECL_CONTEXT for __dynamic_cast appropriately. Like for __cxa_atexit which is similarly lazily declared, I suppose we should push it into the namespace too. Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for trunk? PR c++/106304 gcc/cp/ChangeLog: * constexpr.cc (cxx_dynamic_cast_fn_p): Check for abi_node instead of global_namespace. * rtti.cc (build_dynamic_cast_1): Set DECL_CONTEXT and DECL_SOURCE_LOCATION on dynamic_cast_node, and push it into the namespace. gcc/testsuite/ChangeLog: * g++.dg/modules/pr106304_a.C: New test. * g++.dg/modules/pr106304_b.C: New test. --- gcc/cp/constexpr.cc | 2 +- gcc/cp/rtti.cc | 4 ++++ gcc/testsuite/g++.dg/modules/pr106304_a.C | 12 ++++++++++++ gcc/testsuite/g++.dg/modules/pr106304_b.C | 8 ++++++++ 4 files changed, 25 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/g++.dg/modules/pr106304_a.C create mode 100644 gcc/testsuite/g++.dg/modules/pr106304_b.C diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc index 06dcd71c926..5939d2882f8 100644 --- a/gcc/cp/constexpr.cc +++ b/gcc/cp/constexpr.cc @@ -2108,7 +2108,7 @@ cxx_dynamic_cast_fn_p (tree fndecl) { return (cxx_dialect >= cxx20 && id_equal (DECL_NAME (fndecl), "__dynamic_cast") - && CP_DECL_CONTEXT (fndecl) == global_namespace); + && CP_DECL_CONTEXT (fndecl) == abi_node); } /* Often, we have an expression in the form of address + offset, e.g. diff --git a/gcc/cp/rtti.cc b/gcc/cp/rtti.cc index f5b43ec0fb2..a85c7b56409 100644 --- a/gcc/cp/rtti.cc +++ b/gcc/cp/rtti.cc @@ -787,6 +787,10 @@ build_dynamic_cast_1 (location_t loc, tree type, tree expr, NULL_TREE)); dcast_fn = (build_library_fn_ptr (fn_name, fn_type, ECF_LEAF | ECF_PURE | ECF_NOTHROW)); + /* As with __cxa_atexit in get_atexit_node. */ + DECL_CONTEXT (dcast_fn) = FROB_CONTEXT (current_namespace); + DECL_SOURCE_LOCATION (dcast_fn) = BUILTINS_LOCATION; + dcast_fn = pushdecl (dcast_fn, /*hiding=*/true); pop_abi_namespace (flags); dynamic_cast_node = dcast_fn; } diff --git a/gcc/testsuite/g++.dg/modules/pr106304_a.C b/gcc/testsuite/g++.dg/modules/pr106304_a.C new file mode 100644 index 00000000000..b999eeccf4a --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/pr106304_a.C @@ -0,0 +1,12 @@ +// PR c++/106304 +// { dg-additional-options -fmodules-ts } +// { dg-module-cmi pr106304 } + +export module pr106304; + +struct A { virtual ~A() = default; }; +struct B : A { }; + +inline const B* as_b(const A& a) { + return dynamic_cast<const B*>(&a); +} diff --git a/gcc/testsuite/g++.dg/modules/pr106304_b.C b/gcc/testsuite/g++.dg/modules/pr106304_b.C new file mode 100644 index 00000000000..e8333909c8d --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/pr106304_b.C @@ -0,0 +1,8 @@ +// PR c++/106304 +// { dg-additional-options -fmodules-ts } + +module pr106304; + +void f(A& a) { + as_b(a); +} -- 2.38.0.68.ge85701b4af