| ... | ... | @@ -697,7 +697,7 @@ pub fn writeCurrentStackTrace(options: StackUnwindOptions, writer: *Writer, tty_ |
| 697 | 697 | var printed_any_frame = false; |
| 698 | 698 | while (true) switch (it.next()) { |
| 699 | 699 | .switch_to_fp => |unwind_error| { |
| 700 | | if (StackIterator.fp_unwind_is_safe) continue; // no need to even warn |
| 700 | if (StackIterator.abi_requires_backchain or StackIterator.fp_unwind_is_safe) continue; // no need to even warn |
| 701 | 701 | const module_name = di.getModuleName(di_gpa, unwind_error.address) catch "???"; |
| 702 | 702 | const caption: []const u8 = switch (unwind_error.err) { |
| 703 | 703 | error.MissingDebugInfo => "unwind info unavailable", |
| ... | ... | @@ -855,10 +855,22 @@ const StackIterator = union(enum) { |
| 855 | 855 | } |
| 856 | 856 | } |
| 857 | 857 | |
| 858 | | /// On aarch64-macos, Apple mandate that the frame pointer is always used. |
| 859 | | /// TODO: are there any other architectures with guarantees like this? |
| 858 | /// <https://developer.apple.com/documentation/xcode/writing-arm64-code-for-apple-platforms#Respect-the-purpose-of-specific-CPU-registers> |
| 860 | 859 | const fp_unwind_is_safe = builtin.cpu.arch == .aarch64 and builtin.os.tag.isDarwin(); |
| 861 | 860 | |
| 861 | /// On some architectures, we can do FP unwinding even with `-fomit-frame-pointer` due to ABI |
| 862 | /// requirements. Typically this is because the ABI requires a backchain regardless of whether |
| 863 | /// codegen actually uses a frame pointer for stack frame access. |
| 864 | const abi_requires_backchain = switch (builtin.cpu.arch) { |
| 865 | .hexagon, |
| 866 | .powerpc, |
| 867 | .powerpcle, |
| 868 | .powerpc64, |
| 869 | .powerpc64le, |
| 870 | => true, |
| 871 | else => false, |
| 872 | }; |
| 873 | |
| 862 | 874 | /// Whether the current unwind strategy is allowed given `allow_unsafe`. |
| 863 | 875 | fn stratOk(it: *const StackIterator, allow_unsafe: bool) bool { |
| 864 | 876 | return switch (it.*) { |
| ... | ... | @@ -867,7 +879,7 @@ const StackIterator = union(enum) { |
| 867 | 879 | // immediately regardless of anything. But FPs could also be omitted from a different |
| 868 | 880 | // linked object, so it's not guaranteed to be safe, unless the target specifically |
| 869 | 881 | // requires it. |
| 870 | | .fp => !builtin.omit_frame_pointer and (fp_unwind_is_safe or allow_unsafe), |
| 882 | .fp => abi_requires_backchain or (!builtin.omit_frame_pointer and (fp_unwind_is_safe or allow_unsafe)), |
| 871 | 883 | }; |
| 872 | 884 | } |
| 873 | 885 | |
Alex Rønne Petersen <alex@alexrp.com> 2025-10-03 21:19:38+02:00
lib