[PATCH] D142888: [compiler-rt] Fix building GWPASAN on ARM

[Petr Hosek via Phabricator via llvm-commits]

phosek added inline comments.


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Comment at: compiler-rt/lib/scudo/standalone/CMakeLists.txt:48-55
+  # On ARM, we must link against an unwind lib when GWPAsan is used, otherwise
+  # we get undefined references to __aeabi_unwind_cpp_pr* symbols.
+  # This is because object files compiled with -funwind-tables end up referencing
+  # these symbols on ARM, while on other architectures, such as x86_64 and
+  # AArch64, only the .eh_frame section is added, but no references to an unwind
+  # library are made.
+  if(LIBUNWIND_ENABLE_SHARED OR LIBUNWIND_ENABLE_STATIC)
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Could we use libgcc in this case (and report an error if it's unavailable)? We already have a variable to control whether to use LLVM libunwind or libgcc. This block silently picks up libunwind even when `COMPILER_RT_USE_LLVM_UNWINDER` isn't set which is unexpected.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D142888/new/

https://reviews.llvm.org/D142888