[glibc/azanella/clang] elf: Suppress clang warning on tst-unique4

[Adhemerval Zanella <azanella@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=2d502aefa5e54b89520b2f0593b7122bc784d718

commit 2d502aefa5e54b89520b2f0593b7122bc784d718
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Fri Mar 25 11:21:33 2022 -0300

    elf: Suppress clang warning on tst-unique4
    
    clang warns that the instatiation of the variable is required,
    but no definition is available.  They are implemented on
    tst-unique4lib.so.
    
    Checked on x86_64-linux-gnu.

Diff:
---
 elf/tst-unique4.cc    | 6 ++++++
 elf/tst-unique4lib.cc | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/elf/tst-unique4.cc b/elf/tst-unique4.cc
index 575c70d3a1..ab727b8dbb 100644
--- a/elf/tst-unique4.cc
+++ b/elf/tst-unique4.cc
@@ -2,7 +2,12 @@
 #include "tst-unique4.h"
 
 #include <cstdio>
+#include <libc-diag.h>
 
+/* clang warns that the instatiation of the variable is required, but no
+   definition is available.  They are implemented on tst-unique4lib.so.  */
+DIAG_PUSH_NEEDS_COMMENT_CLANG;
+DIAG_IGNORE_NEEDS_COMMENT_CLANG (13, "-Wundefined-var-template");
 static int a[24] =
   {
     S<1>::i, S<2>::i, S<3>::i, S<4>::i, S<5>::i, S<6>::i, S<7>::i, S<8>::i,
@@ -10,6 +15,7 @@ static int a[24] =
     S<16>::i, S<17>::i, S<18>::i, S<19>::i, S<20>::i, S<21>::i, S<22>::i,
     S<23>::i, S<24>::i
   };
+DIAG_POP_NEEDS_COMMENT_CLANG;
 
 int
 main (void)
diff --git a/elf/tst-unique4lib.cc b/elf/tst-unique4lib.cc
index 17a7cdf567..2829e75cee 100644
--- a/elf/tst-unique4lib.cc
+++ b/elf/tst-unique4lib.cc
@@ -2,7 +2,7 @@
 #include "tst-unique4.h"
 
 template<int N>
-int S<N>::i = N;
+int S<N>::i __attribute__ ((used)) = N;
 template<int N>
 const int S<N>::j __attribute__ ((used)) = -1;