Re: [PATCH v3 10/30] perf clang: Add builtin clang support ant test case

From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: "Wangnan (F)" <wangnan0@huawei.com>,
	Arnaldo Carvalho de Melo <acme@redhat.com>,
	Alexei Starovoitov <ast@fb.com>, Zefan Li <lizefan@huawei.com>,
	He Kuang <hekuang@huawei.com>, Ingo Molnar <mingo@kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	pi3orama <pi3orama@163.com>, Joe Stringer <joe@ovn.org>,
	Jiri Olsa <jolsa@kernel.org>
Subject: Re: [PATCH v3 10/30] perf clang: Add builtin clang support ant test case
Date: Tue, 17 Jan 2017 10:27:39 -0800	[thread overview]
Message-ID: <CAADnVQJnmU3xGBF6pVjp2OV_XK_hirpAa2yrqfqhCARZv6_tcA@mail.gmail.com> (raw)

On Tue, Jan 17, 2017 at 5:38 AM, Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> [acme@jouet linux]$ ls -lah /tmp/perf
> -rwxr-xr-x. 1 acme acme 4.4M Jan 17 10:29 /tmp/perf
> [acme@jouet linux]$ size /tmp/perf
>    text    data     bss     dec     hex filename
> 3954488  622440 23912104        28489032        1b2b548 /tmp/perf
> [acme@jouet linux]$ ldd /tmp/perf | egrep -i llvm\|clang
>         libclangAST.so.40 => /usr/local/lib/libclangAST.so.40 (0x00007f4964981000)
...
>         libLLVMSystemZDisassembler.so.40 => /usr/local/lib/libLLVMSystemZDisassembler.so.40 (0x00007f495fe70000)
...
>         libLLVMSparcDisassembler.so.40 => /usr/local/lib/libLLVMSparcDisassembler.so.40 (0x00007f495f14f000)
...
>         libLLVMPowerPCDisassembler.so.40 => /usr/local/lib/libLLVMPowerPCDisassembler.so.40 (0x00007f495de94000)
...
>         libLLVMMSP430CodeGen.so.40 => /usr/local/lib/libLLVMMSP430CodeGen.so.40 (0x00007f495c79d000)
...
>         libLLVMMipsDisassembler.so.40 => /usr/local/lib/libLLVMMipsDisassembler.so.40 (0x00007f495bf73000)

I think the static binary shouldn't be including all llvm backends.
It's not clear to me why .so pulls them all.
fyi I typically configure llvm with:
-DLLVM_TARGETS_TO_BUILD="X86;BPF"