| Message ID | 20200720201831.3759722-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: abbreviated function template friend matching [PR96106] | expand |
On 7/20/20 4:18 PM, Patrick Palka wrote: > In the below testcase, duplicate_decls wasn't merging the tsubsted > friend declaration for 'void add(auto)' with its definition, because > reduce_template_parm_level (during tsubst_friend_function) lost the > DECL_VIRTUAL_P flag on the invented 'auto' template parameter, which > made template_heads_equivalent_p deem the two template heads as not > equivalent in C++20 mode. > > This patch makes reduce_template_parm_level carry over the > DECL_VIRTUAL_P from the original TEMPLATE_PARM_DECL. > > Passes 'make check-c++' and the cmcstl2 testsuite. Does this look OK > for trunk after a full bootstrap and regtest? OK. > gcc/cp/ChangeLog: > > PR c++/96106 > * pt.c (reduce_template_parm_level): Carry over DECL_VIRTUAL_P > from the original TEMPLATE_PARM_DECL. > > gcc/testsuite/ChangeLog: > > PR c++/96106 > * g++.dg/concepts/abbrev7.C: New test. > --- > gcc/cp/pt.c | 1 + > gcc/testsuite/g++.dg/concepts/abbrev7.C | 14 ++++++++++++++ > 2 files changed, 15 insertions(+) > create mode 100644 gcc/testsuite/g++.dg/concepts/abbrev7.C > > diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c > index defc2a9abd8..3f7b89141b6 100644 > --- a/gcc/cp/pt.c > +++ b/gcc/cp/pt.c > @@ -4453,6 +4453,7 @@ reduce_template_parm_level (tree index, tree type, int levels, tree args, > type); > TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl); > TREE_READONLY (decl) = TREE_READONLY (orig_decl); > + DECL_VIRTUAL_P (decl) = DECL_VIRTUAL_P (orig_decl); > DECL_ARTIFICIAL (decl) = 1; > SET_DECL_TEMPLATE_PARM_P (decl); > > diff --git a/gcc/testsuite/g++.dg/concepts/abbrev7.C b/gcc/testsuite/g++.dg/concepts/abbrev7.C > new file mode 100644 > index 00000000000..443c1b7871b > --- /dev/null > +++ b/gcc/testsuite/g++.dg/concepts/abbrev7.C > @@ -0,0 +1,14 @@ > +// PR c++/96106 > +// { dg-do compile { target concepts } } > + > +template<typename> > +struct number { > + friend void add(auto); > +}; > + > +void add(auto) { } > + > +void foo() { > + number<int> n; > + add(n); // { dg-bogus "ambiguous" } > +} >
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index defc2a9abd8..3f7b89141b6 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -4453,6 +4453,7 @@ reduce_template_parm_level (tree index, tree type, int levels, tree args, type); TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl); TREE_READONLY (decl) = TREE_READONLY (orig_decl); + DECL_VIRTUAL_P (decl) = DECL_VIRTUAL_P (orig_decl); DECL_ARTIFICIAL (decl) = 1; SET_DECL_TEMPLATE_PARM_P (decl); diff --git a/gcc/testsuite/g++.dg/concepts/abbrev7.C b/gcc/testsuite/g++.dg/concepts/abbrev7.C new file mode 100644 index 00000000000..443c1b7871b --- /dev/null +++ b/gcc/testsuite/g++.dg/concepts/abbrev7.C @@ -0,0 +1,14 @@ +// PR c++/96106 +// { dg-do compile { target concepts } } + +template<typename> +struct number { + friend void add(auto); +}; + +void add(auto) { } + +void foo() { + number<int> n; + add(n); // { dg-bogus "ambiguous" } +}