[PATCH] D60372: [gn] Support for building libc++abi

[Petr Hosek via Phabricator via llvm-commits]

phosek added inline comments.


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Comment at: llvm/utils/gn/secondary/libcxxabi/src/BUILD.gn:5
+  # Use exceptions.
+  libcxxabi_enable_exceptions = true
+
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thakis wrote:
> Does this one have to be settable? That seems like an implementation detail from a distance.
We have a concrete use case for this in Fuchsia where we build multiple different variants of libc++ using the multilib layout, including one without exceptions support, see D60926.


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Comment at: llvm/utils/gn/secondary/libcxxabi/src/BUILD.gn:17
+  # Do not export any symbols from the static library.
+  libcxxabi_hermetic_static_library = false
+}
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thakis wrote:
> Wouldn't you always want this? What's an example where one would want to statically link c++abi but export its symbols? They only thing I can think of is when linking it into libc++.dylib, which which case we probably want a toggle for that instead?
> 
> Why is the default false? Why is this settable?
I've tried to match the CMake build where this is disabled by default. I agree with your reasoning but I'm not sure whether we want to deviate from the CMake build?


Repository:
  rCXXA libc++abi

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D60372/new/

https://reviews.llvm.org/D60372