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Fix linking error when compiling for 32-bit watchOS

In https://github.com/rust-lang/rust/pull/124748, I mistakenly conflated
"not SjLj" to mean "ARM EHABI", which isn't true, watchOS armv7k
(specifically only that architecture) uses a third unwinding method
called "DWARF CFI".
This commit is contained in:
Mads Marquart 2024-09-07 17:57:47 +02:00
parent 9afe713695
commit f98ca32b0a
3 changed files with 18 additions and 14 deletions

View file

@ -54,10 +54,10 @@ pub enum EHAction {
Terminate,
}
/// 32-bit Apple ARM uses SjLj exceptions, except for watchOS.
/// 32-bit ARM Darwin platforms uses SjLj exceptions.
///
/// I.e. iOS and tvOS, as those are the only Apple OSes that used 32-bit ARM
/// devices.
/// The exception is watchOS armv7k (specifically that subarchitecture), which
/// instead uses DWARF Call Frame Information (CFI) unwinding.
///
/// <https://github.com/llvm/llvm-project/blob/llvmorg-18.1.4/clang/lib/Driver/ToolChains/Darwin.cpp#L3107-L3119>
pub const USING_SJLJ_EXCEPTIONS: bool =

View file

@ -95,14 +95,15 @@ const UNWIND_DATA_REG: (i32, i32) = (4, 5); // a0, a1
cfg_if::cfg_if! {
if #[cfg(all(
target_arch = "arm",
not(all(target_vendor = "apple", not(target_os = "watchos"))),
not(target_os = "netbsd"),
))] {
target_arch = "arm",
not(target_vendor = "apple"),
not(target_os = "netbsd"),
))] {
/// personality fn called by [ARM EHABI][armeabi-eh]
///
/// Apple 32-bit ARM (but not watchOS) uses the default routine instead
/// since it uses "setjmp-longjmp" unwinding.
/// 32-bit ARM on iOS/tvOS/watchOS does not use ARM EHABI, it uses
/// either "setjmp-longjmp" unwinding or DWARF CFI unwinding, which is
/// handled by the default routine.
///
/// [armeabi-eh]: https://web.archive.org/web/20190728160938/https://infocenter.arm.com/help/topic/com.arm.doc.ihi0038b/IHI0038B_ehabi.pdf
#[lang = "eh_personality"]