[gcc r16-7944] c++: add fixed test [PR39057]

[Marek Polacek via Gcc-cvs]

https://gcc.gnu.org/g:9f99ee9d103dd70c18637271bb7f9b3efc926959

commit r16-7944-g9f99ee9d103dd70c18637271bb7f9b3efc926959
Author: Marek Polacek <pola...@redhat.com>
Date:   Sat Mar 7 12:29:48 2026 -0500

    c++: add fixed test [PR39057]
    
    This was fixed by r16-6725 and we no longer crash.  The error is
    expected.
    
            PR c++/39057
    
    gcc/testsuite/ChangeLog:
    
            * g++.dg/template/friend89.C: New test.

Diff:
---
 gcc/testsuite/g++.dg/template/friend89.C | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/gcc/testsuite/g++.dg/template/friend89.C 
b/gcc/testsuite/g++.dg/template/friend89.C
new file mode 100644
index 000000000000..7c251f6e85b6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/friend89.C
@@ -0,0 +1,11 @@
+// PR c++/39057
+
+struct A
+{
+  template<int> void foo();
+};
+
+template<int> struct B
+{
+  friend void A::foo<0>(int = 0); // { dg-error "friend declaration" }
+};