| Message ID | 20230602142920.1793173-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: is_specialization_of_friend confusion [PR109923] | expand |
On 6/2/23 10:29, Patrick Palka wrote: > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for > trunk? OK. > -- >8 -- > > The check for a non-template member function of a class template in > is_specialization_of_friend is overbroad, and accidentally holds for a > non-template hidden friend too, which causes the predicate to return > true for > > decl = void non_templ_friend(A<int>, A<void>) > friend_decl = void non_templ_friend(A<void>, A<void>) > > This patch refines the check appropriately. > > PR c++/109923 > > gcc/cp/ChangeLog: > > * pt.cc (is_specialization_of_friend): Fix overbroad check for > a non-template member function of a class template. > > gcc/testsuite/ChangeLog: > > * g++.dg/template/friend79.C: New test. > --- > gcc/cp/pt.cc | 1 + > gcc/testsuite/g++.dg/template/friend79.C | 20 ++++++++++++++++++++ > 2 files changed, 21 insertions(+) > create mode 100644 gcc/testsuite/g++.dg/template/friend79.C > > diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc > index 7c2a5647665..a15d1d062c6 100644 > --- a/gcc/cp/pt.cc > +++ b/gcc/cp/pt.cc > @@ -1319,6 +1319,7 @@ is_specialization_of_friend (tree decl, tree friend_decl) > of a template class, we want to check if DECL is a specialization > if this. */ > if (TREE_CODE (friend_decl) == FUNCTION_DECL > + && DECL_CLASS_SCOPE_P (friend_decl) > && DECL_TEMPLATE_INFO (friend_decl) > && !DECL_USE_TEMPLATE (friend_decl)) > { > diff --git a/gcc/testsuite/g++.dg/template/friend79.C b/gcc/testsuite/g++.dg/template/friend79.C > new file mode 100644 > index 00000000000..cd2030df019 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/template/friend79.C > @@ -0,0 +1,20 @@ > +// PR c++/109923 > + > +template<class T> > +struct A { > +private: > + int x; > + > +public: > + A() : x(0) { } > + > + friend void non_templ_friend(A val, A<void> weird) { > + val.x++; // always works > + weird.x++; // { dg-error "private" } should only work when T=void > + } > +}; > + > +int main() { > + non_templ_friend(A<void>(), A<void>()); // { dg-bogus "" } > + non_templ_friend(A<int>(), A<void>()); // { dg-message "required from here" } > +}
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc index 7c2a5647665..a15d1d062c6 100644 --- a/gcc/cp/pt.cc +++ b/gcc/cp/pt.cc @@ -1319,6 +1319,7 @@ is_specialization_of_friend (tree decl, tree friend_decl) of a template class, we want to check if DECL is a specialization if this. */ if (TREE_CODE (friend_decl) == FUNCTION_DECL + && DECL_CLASS_SCOPE_P (friend_decl) && DECL_TEMPLATE_INFO (friend_decl) && !DECL_USE_TEMPLATE (friend_decl)) { diff --git a/gcc/testsuite/g++.dg/template/friend79.C b/gcc/testsuite/g++.dg/template/friend79.C new file mode 100644 index 00000000000..cd2030df019 --- /dev/null +++ b/gcc/testsuite/g++.dg/template/friend79.C @@ -0,0 +1,20 @@ +// PR c++/109923 + +template<class T> +struct A { +private: + int x; + +public: + A() : x(0) { } + + friend void non_templ_friend(A val, A<void> weird) { + val.x++; // always works + weird.x++; // { dg-error "private" } should only work when T=void + } +}; + +int main() { + non_templ_friend(A<void>(), A<void>()); // { dg-bogus "" } + non_templ_friend(A<int>(), A<void>()); // { dg-message "required from here" } +}