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[CMake][Fuchsia] Define asan+noexcept multilib
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Authored by phosek on Jul 3 2019, 10:11 AM.

Details

Summary

Using noexcept multilib with -fno-exceptions can lead to significant
space savings when statically linking libc++abi because we don't need
all the unwinding and demangling code.

When compiling with ASan, we already get a lot of overhead from the
instrumentation itself, when statically linking libc++abi, that overhead
is even larger.

Having the noexcept variant for ASan can help significantly, we've seen
more than 50% size reduction in our system image, which offsets the cost
of having to build another multilib.

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phosek created this revision.Jul 3 2019, 10:11 AM
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This revision is now accepted and ready to land.Jul 3 2019, 10:19 AM
This revision was automatically updated to reflect the committed changes.
Herald added a project: Restricted Project. · View Herald TranscriptJul 13 2019, 1:09 AM