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rprichard added a comment to D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.

Could you add a bit of a comment explaining why the XOM case is not protected against?

I think I can expand on the comment.

libunwind can be used for generating backtraces during regular execution (e.g. profiling) and crashing if the XOM is in use seems unfortunate.

For profiling, I assume the unwind info needs to be accurate at every instruction? I know that's definitely not the case for AArch64, but I thought it's still only mostly-accurate on other archs? I don't *really* know that unwinding through a signal handler is important for Android, but I don't know how to rule it out either, and we do have a test for it. I think the test predated Android's libunwindstack unwinder. Maybe someone could be using _Unwind_Backtrace in a segfault handler, and that probably avoids the async-unwind-info problem most of the time. But I also don't think that's how third-party Android crash dumpers work.

Sure, though, libunwind is generic and is used outside of android as well, including other AArch64 targets, so we do need to consider those use cases while making changes.

Thu, Jan 14, 4:16 PM · Restricted Project, Restricted Project

Wed, Jan 13

rprichard committed rGc82deed6764c: [libunwind] Unwind through aarch64/Linux sigreturn frame (authored by rprichard).
[libunwind] Unwind through aarch64/Linux sigreturn frame
Wed, Jan 13, 4:40 PM
rprichard closed D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.
Wed, Jan 13, 4:39 PM · Restricted Project, Restricted Project

Tue, Jan 12

rprichard added a comment to D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.

Can I get a code-owner to review this?

Tue, Jan 12, 9:45 PM · Restricted Project, Restricted Project
rprichard updated the summary of D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.
Tue, Jan 12, 9:45 PM · Restricted Project, Restricted Project
rprichard updated the diff for D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.

Enable unwind_leaffunction.pass.cpp for AArch64 Linux.

Tue, Jan 12, 9:44 PM · Restricted Project, Restricted Project

Thu, Jan 7

rprichard committed rG658a1be76ba2: [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS (authored by rprichard).
[builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS
Thu, Jan 7, 5:56 PM
rprichard closed D93431: [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS.
Thu, Jan 7, 5:56 PM · Restricted Project

Thu, Dec 17

rprichard retitled D93431: [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS from [builtins] Add COMPILER_RT_BUILTINS_HERMETIC_STATIC_LIBRARY to [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS.
Thu, Dec 17, 4:12 PM · Restricted Project
rprichard updated the diff for D93431: [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS.

Rename flag to COMPILER_RT_BUILTINS_HIDE_SYMBOLS.

Thu, Dec 17, 4:11 PM · Restricted Project
rprichard added a comment to D93467: [ELF] Rename R_TLS to R_TPREL and R_NEG_TLS to R_TPREL_NEG. NFC.

I also think this is a good change.

Thu, Dec 17, 2:35 PM · Restricted Project

Wed, Dec 16

rprichard added inline comments to D93431: [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS.
Wed, Dec 16, 8:38 PM · Restricted Project
rprichard added reviewers for D93431: [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS: kongyi, srhines, compnerd.

I'm using this change in https://android-review.googlesource.com/c/toolchain/llvm_android/+/1532841.

Wed, Dec 16, 5:14 PM · Restricted Project
rprichard requested review of D93431: [builtins] Add COMPILER_RT_BUILTINS_HIDE_SYMBOLS.
Wed, Dec 16, 5:06 PM · Restricted Project

Dec 16 2020

rprichard added a comment to D93331: [ELF] Reject local-exec TLS relocations for -shared.

It looks OK to me.

Dec 16 2020, 2:24 AM · Restricted Project

Dec 11 2020

rprichard added a comment to D56977: [builtins] Do not set hidden attribute on Android.

Keep exporting these symbols on Android for compatibility.

Dec 11 2020, 10:44 PM

Dec 10 2020

rprichard added reviewers for D93003: [libunwind] LIBUNWIND_HERMETIC_STATIC_LIBRARY fixes: phosek, mstorsjo, ldionne.
Dec 10 2020, 1:36 AM · Restricted Project, Restricted Project
rprichard added a comment to D93003: [libunwind] LIBUNWIND_HERMETIC_STATIC_LIBRARY fixes.

I assume the LIBUNWIND_HERMETIC_STATIC_LIBRARY setting isn't used on Darwin -- it leaves unw_* symbols as Extern and not PrivateExtern. Maybe the CMake file could reject that flag on Darwin instead of trying to make it work.

Dec 10 2020, 1:33 AM · Restricted Project, Restricted Project
rprichard retitled D93003: [libunwind] LIBUNWIND_HERMETIC_STATIC_LIBRARY fixes from [libunwind] Fix ELF/Mach-O visibility for unw_getcontext to [libunwind] LIBUNWIND_HERMETIC_STATIC_LIBRARY fixes.
Dec 10 2020, 12:38 AM · Restricted Project, Restricted Project
rprichard updated the diff for D93003: [libunwind] LIBUNWIND_HERMETIC_STATIC_LIBRARY fixes.

Fix LIBUNWIND_HERMETIC_STATIC_LIBRARY on macOS.

Dec 10 2020, 12:37 AM · Restricted Project, Restricted Project

Dec 9 2020

rprichard requested review of D93003: [libunwind] LIBUNWIND_HERMETIC_STATIC_LIBRARY fixes.
Dec 9 2020, 11:14 PM · Restricted Project, Restricted Project

Dec 2 2020

rprichard added a comment to D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.

That could work. Some similar approaches:

  • process_vm_readv
  • pipe+write
  • open /proc/self/mem
Dec 2 2020, 10:37 PM · Restricted Project, Restricted Project
rprichard updated the diff for D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.

Update comments.

Dec 2 2020, 9:27 PM · Restricted Project, Restricted Project

Nov 30 2020

rprichard updated the diff for D91841: [builtins] Define fmax and scalbn inline.

Add +/- to __compiler_rt_scalbnX comment.

Nov 30 2020, 8:47 PM · Restricted Project
rprichard updated the diff for D91841: [builtins] Define fmax and scalbn inline.

Rename new fmax/scalbn fp_lib.h params from a/b to x/y for consistency with the new tests and with the existing __compiler_rt_logb*.

Nov 30 2020, 8:43 PM · Restricted Project
rprichard added inline comments to D91841: [builtins] Define fmax and scalbn inline.
Nov 30 2020, 8:33 PM · Restricted Project

Nov 23 2020

rprichard updated the diff for D91841: [builtins] Define fmax and scalbn inline.

Remove obsoleted crt_fmax[f] and crt_scalbn[f] functions.

Nov 23 2020, 9:03 PM · Restricted Project
rprichard added a comment to D91841: [builtins] Define fmax and scalbn inline.

The __compiler_rt_{logb,scalbn,fmax}* functions don't work with x87 extended-precision FP, and I think FPUtil would handle that. Perhaps the existing inline functions could be extended to support x87, though.

Nov 23 2020, 8:59 PM · Restricted Project

Nov 19 2020

rprichard added a comment to D91841: [builtins] Define fmax and scalbn inline.

The existing __compiler_rt_logb* inline functions were also added to address PR32279, in D49514. On Android, all of fmax*/logb*/scalbn* are in libm, not libc. I commented more on the bug: https://bugs.llvm.org/show_bug.cgi?id=32279#c7.

Nov 19 2020, 11:35 PM · Restricted Project
rprichard added reviewers for D91841: [builtins] Define fmax and scalbn inline: compnerd, scanon, rupprecht, efriedma.
Nov 19 2020, 11:29 PM · Restricted Project
rprichard updated the diff for D91841: [builtins] Define fmax and scalbn inline.

Switch scalbn calls in ppc/divtc3.c to __compiler_rt_scalbn. I verified that, after doing so, libclang_rt.builtins-powerpc64le.a has no unresolved symbols for fmax*/logb*/scalbn*.

Nov 19 2020, 11:22 PM · Restricted Project
rprichard added a comment to D91841: [builtins] Define fmax and scalbn inline.

With this change, I think PR32279 is still an issue with non-standard FP formats, like the x86 80-bit extended-precision format. In principle, it seems straightforward to extend the __compiler_rt_* inline functions to handle that format.

Nov 19 2020, 9:47 PM · Restricted Project
rprichard requested review of D91841: [builtins] Define fmax and scalbn inline.
Nov 19 2020, 9:17 PM · Restricted Project

Nov 10 2020

rprichard added a comment to D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.

Could you add a bit of a comment explaining why the XOM case is not protected against?

Nov 10 2020, 12:14 AM · Restricted Project, Restricted Project

Nov 5 2020

rprichard requested review of D90898: [libunwind] Unwind through aarch64/Linux sigreturn frame.
Nov 5 2020, 8:27 PM · Restricted Project, Restricted Project

Sep 24 2020

rprichard added inline comments to D85005: [libunwind] Support DW_CFA_remember/restore_state without heap allocation..
Sep 24 2020, 2:49 PM · Restricted Project, Restricted Project

Sep 23 2020

rprichard committed rG881aba7071c6: [libunwind] Optimize dl_iterate_phdr's findUnwindSectionsByPhdr (authored by rprichard).
[libunwind] Optimize dl_iterate_phdr's findUnwindSectionsByPhdr
Sep 23 2020, 3:42 PM
rprichard committed rGb16d6653c01c: [libunwind] Combine dl_iterate_phdr codepaths for DWARF and EHABI (authored by rprichard).
[libunwind] Combine dl_iterate_phdr codepaths for DWARF and EHABI
Sep 23 2020, 3:42 PM
rprichard closed D87881: [libunwind] Optimize dl_iterate_phdr's findUnwindSectionsByPhdr.
Sep 23 2020, 3:42 PM · Restricted Project, Restricted Project
rprichard closed D87880: [libunwind] Combine dl_iterate_phdr codepaths for DWARF and EHABI.
Sep 23 2020, 3:42 PM · Restricted Project, Restricted Project

Sep 21 2020

rprichard added a comment to D87880: [libunwind] Combine dl_iterate_phdr codepaths for DWARF and EHABI.

Thanks for the review. It looks like I still need someone from the libunwind group to accept it, though.

Sep 21 2020, 4:03 PM · Restricted Project, Restricted Project
rprichard added a comment to D87881: [libunwind] Optimize dl_iterate_phdr's findUnwindSectionsByPhdr.

Thanks for the review. It looks like I still need someone from the libunwind group to accept it, though.

Sep 21 2020, 4:03 PM · Restricted Project, Restricted Project

Sep 17 2020

rprichard added a comment to D87881: [libunwind] Optimize dl_iterate_phdr's findUnwindSectionsByPhdr.

I uploaded the Android benchmark I used: https://gist.github.com/rprichard/1688de36f0132a40294adb0409189533.

Sep 17 2020, 9:31 PM · Restricted Project, Restricted Project
rprichard requested review of D87881: [libunwind] Optimize dl_iterate_phdr's findUnwindSectionsByPhdr.
Sep 17 2020, 9:19 PM · Restricted Project, Restricted Project
rprichard added a reviewer for D87880: [libunwind] Combine dl_iterate_phdr codepaths for DWARF and EHABI: saugustine.

This change enables the FrameHeaderCache for EHABI.

Sep 17 2020, 9:18 PM · Restricted Project, Restricted Project
rprichard updated the diff for D87880: [libunwind] Combine dl_iterate_phdr codepaths for DWARF and EHABI.

Apply clang-format fix.

Sep 17 2020, 9:17 PM · Restricted Project, Restricted Project
rprichard requested review of D87880: [libunwind] Combine dl_iterate_phdr codepaths for DWARF and EHABI.
Sep 17 2020, 9:16 PM · Restricted Project, Restricted Project
rprichard added a comment to D83573: [libunwind] Support for leaf function unwinding..

I think these libunwind tests are relying on the signal trampoline having "good enough" unwind info, but AFAIK, that's not the case with the signal trampoline (__kernel_rt_sigreturn) in the AArch64 Linux vDSO. There was a commit recently adjusting .cfi_startproc to let the unwinder find the vDSO's FDE, but then this was quickly reverted. The FDE change allowed libgcc to find the FDE, and that broke glibc pthread cancellation somehow, so the FDE was then removed:

Sep 17 2020, 5:01 PM · Restricted Project, Restricted Project

Sep 16 2020

rprichard abandoned D86256: [libunwind] Make .eh_frame scanning/caching optional.

Abandoned in favor of D87750.

Sep 16 2020, 7:03 PM · Restricted Project, Restricted Project
rprichard committed rGfb1abe00635c: [libunwind][DWARF] Fix end of .eh_frame calculation (authored by rprichard).
[libunwind][DWARF] Fix end of .eh_frame calculation
Sep 16 2020, 7:02 PM
rprichard closed D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.
Sep 16 2020, 7:02 PM · Restricted Project, Restricted Project
rprichard added a comment to D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.

This seems like a bad name.

Sep 16 2020, 4:37 PM · Restricted Project, Restricted Project
rprichard updated the diff for D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.

Rename dso_length to text_segment_length.

Sep 16 2020, 4:29 PM · Restricted Project, Restricted Project
rprichard updated subscribers of D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.

Adding @saugustine -- this patch makes the frame header cache one word larger per entry.

Sep 16 2020, 2:29 AM · Restricted Project, Restricted Project
rprichard updated the summary of D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.
Sep 16 2020, 2:26 AM · Restricted Project, Restricted Project
rprichard updated the diff for D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.

Stylistic change.

Sep 16 2020, 2:26 AM · Restricted Project, Restricted Project
rprichard added a comment to D86256: [libunwind] Make .eh_frame scanning/caching optional.

I uploaded D87750, an alternative to this patch.

Sep 16 2020, 2:24 AM · Restricted Project, Restricted Project
rprichard added a comment to D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.

An alternative to D86256.

Sep 16 2020, 2:24 AM · Restricted Project, Restricted Project
rprichard requested review of D87750: [libunwind][DWARF] Fix end of .eh_frame calculation.
Sep 16 2020, 2:04 AM · Restricted Project, Restricted Project

Sep 15 2020

rprichard added a comment to D86256: [libunwind] Make .eh_frame scanning/caching optional.

Just want to comment "Or use LLD, which automatically inserts the terminator" - the zero terminator CIE is to work around a glibc issue D46566

Sep 15 2020, 7:54 PM · Restricted Project, Restricted Project

Sep 14 2020

rprichard added a comment to D86256: [libunwind] Make .eh_frame scanning/caching optional.

The commit description talks about making the caching optional, but I don't really see that aspect in the patch - or maybe I'm just not studying it closely enough?

Sep 14 2020, 5:17 PM · Restricted Project, Restricted Project
rprichard added a comment to D75795: [libc++abi] Change __cxa_finalize return type to void.

I think I'm fine with this revision. I was wondering if the two functions should be removed from the GNU libsupc++'s cxxabi.h as well, which also declares both of the functions with an int return type. (i.e. It has the same issue as LLVM's cxxabi.h.)

Sep 14 2020, 2:44 PM · Restricted Project, Restricted Project, Restricted Project

Sep 9 2020

rprichard committed rG09d492902f17: [libunwind] Bare-metal DWARF: set dso_base to 0 (authored by rprichard).
[libunwind] Bare-metal DWARF: set dso_base to 0
Sep 9 2020, 3:44 PM
rprichard closed D86748: [libunwind] Bare-metal DWARF: set dso_base to 0.
Sep 9 2020, 3:44 PM · Restricted Project, Restricted Project
rprichard updated the summary of D86748: [libunwind] Bare-metal DWARF: set dso_base to 0.
Sep 9 2020, 3:38 PM · Restricted Project, Restricted Project
rprichard added inline comments to D86748: [libunwind] Bare-metal DWARF: set dso_base to 0.
Sep 9 2020, 3:34 PM · Restricted Project, Restricted Project

Sep 8 2020

rprichard updated the diff for D86748: [libunwind] Bare-metal DWARF: set dso_base to 0.

Use -1 to indicate "search all cache entries".

Sep 8 2020, 8:40 PM · Restricted Project, Restricted Project
rprichard added a comment to D86748: [libunwind] Bare-metal DWARF: set dso_base to 0.

Why not use -1 as the indicator instead of 0?

Sep 8 2020, 8:39 PM · Restricted Project, Restricted Project
rprichard committed rG88bf133c99c3: [libunwind] Replace chain-of-ifdefs for dl_iterate_phdr (authored by rprichard).
[libunwind] Replace chain-of-ifdefs for dl_iterate_phdr
Sep 8 2020, 3:50 PM
rprichard closed D86768: [libunwind] Replace chain-of-ifdefs for dl_iterate_phdr.
Sep 8 2020, 3:50 PM · Restricted Project, Restricted Project

Sep 3 2020

rprichard added a comment to D86256: [libunwind] Make .eh_frame scanning/caching optional.

The Linux ABI Extensions spec describes the binary search table of .eh_frame_hdr as optional, so maybe falling back to .eh_frame scanning could be necessary to accommodate some ELF files? I wonder what situation results in an omitted search table. ld.bfd does have code for outputting .eh_frame_hdr without a search table.

Sep 3 2020, 10:05 PM · Restricted Project, Restricted Project
rprichard committed rG673484b34189: [libunwind] Minor SJLJ config cleanup. NFCI. (authored by rprichard).
[libunwind] Minor SJLJ config cleanup. NFCI.
Sep 3 2020, 4:00 PM
rprichard closed D86767: [libunwind] Minor SJLJ config cleanup. NFCI..
Sep 3 2020, 4:00 PM · Restricted Project, Restricted Project

Sep 2 2020

rprichard added a comment to D86766: [libunwind] Fix a few libunwind includes.

On second thought, maybe I don't actually need this change, and the includes still seem like a mess in libunwind. Maybe it makes more sense to do a larger revision eventually.

Sep 2 2020, 10:52 PM · Restricted Project, Restricted Project
rprichard updated the diff for D86768: [libunwind] Replace chain-of-ifdefs for dl_iterate_phdr.

I am going to accept this, since no one else seems to be able to review it. But the problem here is that no one really knows what a simplified ifdef chain with the same functionality looks like. I tried a couple of times and failed miserably.

So if this works, great! If not, we will need to revert it quickly.

Sep 2 2020, 10:13 PM · Restricted Project, Restricted Project
rprichard added reviewers for D86768: [libunwind] Replace chain-of-ifdefs for dl_iterate_phdr: phosek, jgorbe.
Sep 2 2020, 4:36 PM · Restricted Project, Restricted Project
rprichard added a reviewer for D86767: [libunwind] Minor SJLJ config cleanup. NFCI.: phosek.

Do I need an approval from a libunwind group member?

Sep 2 2020, 3:59 PM · Restricted Project, Restricted Project

Aug 28 2020

rprichard updated the summary of D86767: [libunwind] Minor SJLJ config cleanup. NFCI..
Aug 28 2020, 5:57 PM · Restricted Project, Restricted Project
rprichard updated the diff for D86767: [libunwind] Minor SJLJ config cleanup. NFCI..

Remove most of the previous change. Add a comment about Apple/armv7k.

Aug 28 2020, 5:57 PM · Restricted Project, Restricted Project
rprichard added a comment to D86767: [libunwind] Minor SJLJ config cleanup. NFCI..

Sorry for the inconvenience that libunwind is not really buildable for armv7 from iOS SDK. You can build a single threaded version without referring to those interfaces. If this is really troublesome for you, feel free to file a bug report and we can see what can be done here.

Aug 28 2020, 5:26 PM · Restricted Project, Restricted Project
rprichard updated the summary of D86256: [libunwind] Make .eh_frame scanning/caching optional.
Aug 28 2020, 3:04 AM · Restricted Project, Restricted Project
rprichard added a comment to D86256: [libunwind] Make .eh_frame scanning/caching optional.

If the unwinder uses dl_iterate_phdr, then entries that are automatically added to DwarfFDECache would become invalid if the module containing the entry were unloaded. (On Apple systems, DwarfFDECache registers dyldUnloadHook to remove unloaded entries.)

Aug 28 2020, 2:29 AM · Restricted Project, Restricted Project
rprichard added a reviewer for D86768: [libunwind] Replace chain-of-ifdefs for dl_iterate_phdr: saugustine.
Aug 28 2020, 1:33 AM · Restricted Project, Restricted Project
rprichard updated subscribers of D86256: [libunwind] Make .eh_frame scanning/caching optional.

FWIW, when compact unwinding defers to DWARF (compactSaysUseDwarf), the unwinder begins a scan of .eh_frame at a given offset. Is that really the right behavior, or will the offset always point directly at the appropriate FDE (as with the DWARF index .eh_frame_hdr)?

Aug 28 2020, 1:27 AM · Restricted Project, Restricted Project
rprichard updated subscribers of D86767: [libunwind] Minor SJLJ config cleanup. NFCI..

FWIW, I compiled libunwind for Darwin, and I had trouble getting it to compile for armv7. Unwind-sjlj.c needs these things:

  • #include <System/pthread_machdep.h>
  • _pthread_getspecific_direct(__PTK_LIBC_DYLD_Unwind_SjLj_Key)
Aug 28 2020, 1:16 AM · Restricted Project, Restricted Project
rprichard retitled D86256: [libunwind] Make .eh_frame scanning/caching optional from [libunwind] Refactor DWARF FDE lookup to [libunwind] Make .eh_frame scanning/caching optional.
Aug 28 2020, 12:56 AM · Restricted Project, Restricted Project
rprichard updated the diff for D86257: [libunwind] Split out UnwindInfoSections and dl_iterate_phdr lookup.

Rebase this change.

Aug 28 2020, 12:54 AM · Restricted Project, Restricted Project
rprichard updated the diff for D86256: [libunwind] Make .eh_frame scanning/caching optional.

Split out the chain-of-ifdefs change into D86768.

Aug 28 2020, 12:53 AM · Restricted Project, Restricted Project
rprichard requested review of D86768: [libunwind] Replace chain-of-ifdefs for dl_iterate_phdr.
Aug 28 2020, 12:53 AM · Restricted Project, Restricted Project
rprichard requested review of D86767: [libunwind] Minor SJLJ config cleanup. NFCI..
Aug 28 2020, 12:52 AM · Restricted Project, Restricted Project
rprichard requested review of D86766: [libunwind] Fix a few libunwind includes.
Aug 28 2020, 12:50 AM · Restricted Project, Restricted Project

Aug 27 2020

rprichard requested review of D86748: [libunwind] Bare-metal DWARF: set dso_base to 0.
Aug 27 2020, 4:22 PM · Restricted Project, Restricted Project

Aug 26 2020

rprichard committed rG3071d5ffba23: [libunwind] Factor out getInfoFromFdeCie. NFCI. (authored by rprichard).
[libunwind] Factor out getInfoFromFdeCie. NFCI.
Aug 26 2020, 6:24 PM
rprichard committed rG7a457593efec: [libunwind] Minor fixes in libunwind (authored by rprichard).
[libunwind] Minor fixes in libunwind
Aug 26 2020, 6:24 PM
rprichard closed D86255: [libunwind] Factor out getInfoFromFdeCie. NFCI..
Aug 26 2020, 6:24 PM · Restricted Project, Restricted Project
rprichard closed D86254: [libunwind] Minor fixes in libunwind.
Aug 26 2020, 6:24 PM · Restricted Project, Restricted Project

Aug 25 2020

rprichard added a comment to D86372: [libunwind] Make findUnwindSectionsByPhdr static.

From the discussion on D86254, this should be cherry-picked to 11.x right?

Correct. This findUnwindSectionsByPhdr change (D86372) is needed for 11.

Aug 25 2020, 4:17 AM · Restricted Project, Restricted Project

Aug 24 2020

rprichard added a comment to D86411: [libunwind] Remove static_assert / __has_feature macros.

Oh, ok, I see - maybe CMake deduced that the option wasn't needed in my case, when building with a compiler that defaults to a new enough version.

Aug 24 2020, 4:15 PM · Restricted Project, Restricted Project
rprichard committed rG9e32d7b6e7e6: [libunwind] Remove static_assert / __has_feature macros (authored by rprichard).
[libunwind] Remove static_assert / __has_feature macros
Aug 24 2020, 2:08 PM
rprichard closed D86411: [libunwind] Remove static_assert / __has_feature macros.
Aug 24 2020, 2:08 PM · Restricted Project, Restricted Project