[cfe-users] Using libunwind

[Ben Pope]

How do I build clang/libc++/libc++abi/libunwind/compiler-rt without 
requiring libgcc_s?

Do I need --rtlib=compiler-rt somewhere?

I build like this:

cmake -GNinja -DCMAKE_BUILD_TYPE=Release -DLIBCXX_CXX_ABI=libcxxabi 
-DLIBCXXABI_USE_LLVM_UNWINDER=YES 
-DLIBCXX_CXX_ABI_INCLUDE_PATHS=../../llvm/projects/libcxxabi/include 
-DLIT_EXECUTABLE=../../llvm/utils/lit/lit.py 
-DLLVM_CONFIG_PATH=../../llvm/tools.llvm-config 
-DCMAKE_C_COMPILER=clang-3.7 -DCMAKE_CXX_COMPILER=clang++-3.7 
-DCMAKE_INSTALL_PREFIX=../../install/release ../../llvm/

And end up with:

ben at yyls03:~/development/test$ ldd 
~/development/llvm/trunk/build/release/lib/libunwind.so
	linux-vdso.so.1 =>  (0x00007fffdf168000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f42a0203000)
	libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f429ffff000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 
(0x00007f429fde0000)
	/lib64/ld-linux-x86-64.so.2 (0x00007f42a0600000)
ben at yyls03:~/development/test$ ldd 
~/development/llvm/trunk/build/release/lib/libc++abi.so
	linux-vdso.so.1 =>  (0x00007ffcc90c2000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fe3fad53000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 
(0x00007fe3fab35000)
	libunwind.so.1 => 
/home/ben/development/llvm/trunk/build/release/lib/../lib/libunwind.so.1 
(0x00007fe3fab27000)
	libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fe3fa923000)
	/lib64/ld-linux-x86-64.so.2 (0x00007fe3fb18f000)
ben at yyls03:~/development/test$ ldd 
~/development/llvm/trunk/build/release/lib/libc++.so
	linux-vdso.so.1 =>  (0x00007ffd3bfc1000)
	libc++abi.so.1 => 
/home/ben/development/llvm/trunk/build/release/lib/../lib/libc++abi.so.1 
(0x00007fe8077aa000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 
(0x00007fe807563000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fe80719d000)
	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fe806e97000)
	librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007fe806c8f000)
	libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007fe806a77000)
	libunwind.so.1 => 
/home/ben/development/llvm/trunk/build/release/lib/../lib/../lib/libunwind.so.1 
(0x00007fe806a6a000)
	libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fe806865000)
	/lib64/ld-linux-x86-64.so.2 (0x00007fe8078b8000)

Is it correct that libc++ depends on libgcc_s?

Ben