[binutils-gdb] [gdb/testsuite] Use Wno-non-c-typedef-for-linkage for gcc 16

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=44df4c640694765fc028bdb0c64d346638466eab

commit 44df4c640694765fc028bdb0c64d346638466eab
Author: Tom de Vries <[email protected]>
Date:   Sat May 30 14:46:22 2026 +0200

    [gdb/testsuite] Use Wno-non-c-typedef-for-linkage for gcc 16
    
    With gcc 16 and test-case gdb.cp/classes.exp I run into:
    ...
    classes.cc:440:15: warning: anonymous non-C-compatible type given name for linkage purposes by 'typedef' declaration [-Wnon-c-typedef-for-linkage]^M
      440 | typedef class {^M
          |               ^^M
          |               DynamicBase2^M
    classes.cc:443:15: note: type is not C-compatible because it contains 'virtual int DynamicBase2::get_x()' declaration^M
      443 |   virtual int get_x () { return x; }^M
          |               ^~~~~^M
    ...
    
    Fix this by applying Wno-non-c-typedef-for-linkage, which is already done for
    clang.
    
    Likewise for gdb.cp/class2.exp.
    
    Reviewed-By: Keith Seitz <[email protected]>
    
    Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=34187

Diff:
---
 gdb/testsuite/gdb.cp/class2.exp  | 8 +++++---
 gdb/testsuite/gdb.cp/classes.exp | 9 ++++++---
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/gdb/testsuite/gdb.cp/class2.exp b/gdb/testsuite/gdb.cp/class2.exp
index 705f51ac3e0..0d434fde174 100644
--- a/gdb/testsuite/gdb.cp/class2.exp
+++ b/gdb/testsuite/gdb.cp/class2.exp
@@ -19,9 +19,11 @@ require allow_cplus_tests
 standard_testfile .cc
 
 set flags [list debug c++]
-# When using recent Clangs, this test fails to compile without this warning
-# being disabled.  However, older Clangs fail to recognize the flag.
-if { [gcc_major_version "clang-*" "c++"] > 10 } {
+# When using recent Clangs/GCCs, this test fails to compile without this
+# warning being disabled.  However, older Clangs/GCCs fail to recognize the
+# flag.
+if { [gcc_major_version "clang-*" "c++"] > 10
+     || [gcc_major_version "gcc-*" "c++"] >= 16} {
     lappend flags additional_flags=-Wno-non-c-typedef-for-linkage
 }
 
diff --git a/gdb/testsuite/gdb.cp/classes.exp b/gdb/testsuite/gdb.cp/classes.exp
index 71ce810adad..d2fb7c0c14c 100644
--- a/gdb/testsuite/gdb.cp/classes.exp
+++ b/gdb/testsuite/gdb.cp/classes.exp
@@ -25,12 +25,15 @@ load_lib "cp-support.exp"
 standard_testfile .cc
 
 set flags [list debug c++]
+
 set clang_used false
 if { [test_compiler_info "clang-*" "c++"] } {
     set clang_used true
-    if { [gcc_major_version "clang-*" "c++"] >= 11} {
-	lappend flags additional_flags=-Wno-non-c-typedef-for-linkage
-    }
+}
+
+if { [gcc_major_version "clang-*" "c++"] >= 11
+     || [gcc_major_version "gcc-*" "c++"] >= 16} {
+    lappend flags additional_flags=-Wno-non-c-typedef-for-linkage
 }
 
 if {[prepare_for_testing "failed to prepare" $testfile $srcfile $flags]} {