From e89055f90cff9fb6f565b9374e1ab74f805682fb Mon Sep 17 00:00:00 2001 From: Jason Merrill Date: Fri, 9 Apr 2021 16:43:50 -0400 Subject: c++: pack in base-specifier in lambda [PR100006] Normally cp_parser_base_clause prevents unexpanded packs, but in a lambda check_for_bare_parameter_packs allows it. Then we weren't finding the pack when scanning the lambda body. This doesn't fix a valid variant like template void sink (Ts&&...); template void f() { sink ([] { struct S : Ts { }; }...); } int main() { f(); } but that's a much bigger project. gcc/cp/ChangeLog: PR c++/100006 * pt.c (find_parameter_packs_r) [TAG_DEFN]: Look into bases. gcc/testsuite/ChangeLog: PR c++/100006 * g++.dg/cpp0x/lambda/lambda-variadic13.C: New test. --- gcc/cp/pt.c | 9 +++++++++ gcc/testsuite/g++.dg/cpp0x/lambda/lambda-variadic13.C | 11 +++++++++++ 2 files changed, 20 insertions(+) create mode 100644 gcc/testsuite/g++.dg/cpp0x/lambda/lambda-variadic13.C (limited to 'gcc') diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index 01c807b..b32833003 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -4061,6 +4061,15 @@ find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data) *walk_subtrees = 0; return NULL_TREE; + case TAG_DEFN: + /* Local class, need to look through the whole definition. */ + t = TREE_TYPE (t); + if (CLASS_TYPE_P (t)) + for (tree bb : BINFO_BASE_BINFOS (TYPE_BINFO (t))) + cp_walk_tree (&BINFO_TYPE (bb), &find_parameter_packs_r, + ppd, ppd->visited); + return NULL_TREE; + default: return NULL_TREE; } diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-variadic13.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-variadic13.C new file mode 100644 index 0000000..ac4e631 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-variadic13.C @@ -0,0 +1,11 @@ +// PR c++/100006 +// { dg-do compile { target c++14 } } + +template +void f() { + [] { struct S : Ts { }; }; // { dg-error "not expanded" } +} + +int main() { + f<>(); +} -- cgit v1.1