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From: Kui-Feng Lee <thinker.li@gmail.com>
To: bpf@vger.kernel.org, ast@kernel.org, martin.lau@linux.dev,
	song@kernel.org, kernel-team@meta.com, andrii@kernel.org
Cc: sinquersw@gmail.com, kuifeng@meta.com,
	Kui-Feng Lee <thinker.li@gmail.com>,
	yhs@meta.com
Subject: [PATCH bpf-next] bpftool: cast pointers for shadow types explicitly.
Date: Mon, 11 Mar 2024 18:37:26 -0700	[thread overview]
Message-ID: <20240312013726.1780720-1-thinker.li@gmail.com> (raw)

According to a report, skeletons fail to assign shadow pointers when being
compiled with C++ programs. Unlike C doing implicit casting for void
pointers, C++ requires an explicit casting.

To support C++, we do explicit casting for each shadow pointer.

Cc: yhs@meta.com
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
---
 tools/bpf/bpftool/gen.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c
index 4fa4ade1ce74..dedafea0c127 100644
--- a/tools/bpf/bpftool/gen.c
+++ b/tools/bpf/bpftool/gen.c
@@ -1131,7 +1131,7 @@ static void gen_st_ops_shadow_init(struct btf *btf, struct bpf_object *obj)
 			continue;
 		codegen("\
 			\n\
-				obj->struct_ops.%1$s = bpf_map__initial_value(obj->maps.%1$s, NULL);\n\
+				obj->struct_ops.%1$s = (typeof(obj->struct_ops.%1$s))bpf_map__initial_value(obj->maps.%1$s, NULL);\n\
 			\n\
 			", ident);
 	}
-- 
2.34.1


             reply	other threads:[~2024-03-12  1:37 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-12  1:37 Kui-Feng Lee [this message]
2024-03-12  5:22 ` [PATCH bpf-next] bpftool: cast pointers for shadow types explicitly Yonghong Song
2024-03-12  9:53   ` Quentin Monnet
2024-03-12 22:47 ` Andrii Nakryiko
2024-03-13  0:07   ` Kui-Feng Lee
2024-03-13  0:27     ` Andrii Nakryiko
2024-03-13  0:37       ` Kui-Feng Lee
2024-03-13 15:51         ` Andrii Nakryiko
2024-03-14 20:36           ` Andrii Nakryiko
2024-03-14 20:40 ` patchwork-bot+netdevbpf

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