[PATCH] D25402: [Driver] Pass -lunwind when using libc++ + compiler-rt on Linux

[Jonas Hahnfeld via cfe-commits]

Hahnfeld added inline comments.


================
Comment at: lib/Driver/ToolChains.cpp:4704
+      GetRuntimeLibType(Args) == ToolChain::RLT_CompilerRT)
+    CmdArgs.push_back("-lunwind");
+}
----------------
mgorny wrote:
> Hahnfeld wrote:
> > As just written in D25008: This will probably result in problems if a system default `libunwind.so.8` is installed...
> I think this is the correct behavior in this case. Clang should work with whichever unwinder implementation is available, and if you want to change that, change the `libunwind.so` symlink.
> 
> However, I don't really think it's a good idea to have both unwinder libraries installed alongside, especially that they are sharing the same name.
No, we can't: The nongnu libunwind is used by other system libraries that need and are tested against this version.

It's certainly not a good idea, but it's reality in many distros. Most of them don't ship LLVM's libunwind.


https://reviews.llvm.org/D25402