From: Yonghong Song <yhs@fb.com>
Date: Wed, 8 Dec 2021 21:04:03 -0800
Subject: selftests/bpf: Fix a compilation warning
Patch-mainline: v5.17-rc1
Git-commit: b540358e6c4d86eb450f3539aea198653e656641
References: jsc#PED-1368

The following warning is triggered when I used clang compiler
to build the selftest.

  /.../prog_tests/btf_dedup_split.c:368:6: warning: variable 'btf2' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
        if (!ASSERT_OK(err, "btf_dedup"))
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /.../prog_tests/btf_dedup_split.c:424:12: note: uninitialized use occurs here
        btf__free(btf2);
                  ^~~~
  /.../prog_tests/btf_dedup_split.c:368:2: note: remove the 'if' if its condition is always false
        if (!ASSERT_OK(err, "btf_dedup"))
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /.../prog_tests/btf_dedup_split.c:343:25: note: initialize the variable 'btf2' to silence this warning
        struct btf *btf1, *btf2;
                               ^
                                = NULL

Initialize local variable btf2 = NULL and the warning is gone.

Fixes: 9a49afe6f5a5 ("selftests/bpf: Add btf_dedup case with duplicated structs within CU")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211209050403.1770836-1-yhs@fb.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c
@@ -340,7 +340,7 @@ static void btf_add_dup_struct_in_cu(str
 
 static void test_split_dup_struct_in_cu()
 {
-	struct btf *btf1, *btf2;
+	struct btf *btf1, *btf2 = NULL;
 	int err;
 
 	/* generate the base data.. */