commit 3751474686ba0d2cc7b8a4086114332cbc36e29c Author: Georg Koppen gk@torproject.org Date: Thu Jun 14 11:26:47 2018 +0000

Bug 26329: Fix Rust cross-compilation for 32bit Windows --- projects/rust/build | 4 +- projects/rust/config | 2 +- projects/rust/panic-abort.patch | 36 ---------- projects/rust/unwind.patch | 154 ++++++++++++++++++++++++++++++++++++++++ 4 files changed, 157 insertions(+), 39 deletions(-)

diff --git a/projects/rust/build b/projects/rust/build index 74ce74a..af0f62b 100644 --- a/projects/rust/build +++ b/projects/rust/build @@ -65,8 +65,8 @@ cd /var/tmp/build/rustc-[% c('version') %]-src # toolchains on Linux, targeting Windows 32bit, use SjLj unwinding. # See: https://github.com/rust-lang/rust/issues/12859 for discussion about # that and https://github.com/rust-lang/rust/pull/49633 for a newer attempt to - # fix this problem. - patch -p1 < $rootdir/panic-abort.patch + # fix this problem. We backport and apply the patch from neersighted. + patch -p1 < $rootdir/unwind.patch [% END %]

mkdir build diff --git a/projects/rust/config b/projects/rust/config index 9d3030d..771b50b 100644 --- a/projects/rust/config +++ b/projects/rust/config @@ -73,5 +73,5 @@ input_files: gpg_keyring: rust.gpg - filename: binaryen.patch enable: '[% c("var/linux") %]' - - filename: panic-abort.patch + - filename: unwind.patch enable: '[% c("var/windows-i686") %]' diff --git a/projects/rust/panic-abort.patch b/projects/rust/panic-abort.patch deleted file mode 100644 index 1711ff7..0000000 --- a/projects/rust/panic-abort.patch +++ /dev/null @@ -1,36 +0,0 @@ -From 2fe471643721f3967f1bdf28907b0a7247fdb705 Mon Sep 17 00:00:00 2001 -From: Georg Koppen gk@torproject.org -Date: Thu, 26 Apr 2018 13:18:27 +0000 -Subject: [PATCH] Avoid cross-compilation breakage due to unwinding - incompatibilities - - -diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs -index 55d104b182..85330f973b 100644 ---- a/src/bootstrap/bin/rustc.rs -+++ b/src/bootstrap/bin/rustc.rs -@@ -143,7 +143,8 @@ fn main() { - // workaround undefined references to `rust_eh_unwind_resume` generated - // otherwise, see issue https://github.com/rust-lang/rust/issues/43095. - if crate_name == "panic_abort" || -- crate_name == "compiler_builtins" && stage != "0" { -+ crate_name == "compiler_builtins" && stage != "0" || -+ target == "i686-pc-windows-gnu" { - cmd.arg("-C").arg("panic=abort"); - } - -diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs -index 9ea5f39b71..bb689120af 100644 ---- a/src/libtest/lib.rs -+++ b/src/libtest/lib.rs -@@ -45,7 +45,6 @@ extern crate getopts; - extern crate term; - #[cfg(any(unix, target_os = "cloudabi"))] - extern crate libc; --extern crate panic_unwind; - - pub use self::TestFn::*; - pub use self::ColorConfig::*; --- -2.17.0 - diff --git a/projects/rust/unwind.patch b/projects/rust/unwind.patch new file mode 100644 index 0000000..8e2e0fc --- /dev/null +++ b/projects/rust/unwind.patch @@ -0,0 +1,154 @@ +From f967c575e502e507ed51b7ed8d1e2a08525e6ae6 Mon Sep 17 00:00:00 2001 +From: Bjorn Neergaard bjorn@neersighted.com +Date: Tue, 3 Apr 2018 19:01:07 -0600 +Subject: [PATCH] Fix cross-compiling i686-pc-windows-gnu from Linux + +This is still very rough and serves as a proof-of-concept for fixing +Linux -> 32-bit MinGW cross compilation workflow. Currently, clang and +GCC's MinGW targets both only support DW2 (DWARF) or SJLJ (Set Jump Long +Jump) unwinding on 32-bit Windows. + +The default for GCC (and the way it is shipped on every major distro) is +to use SJLJ on Windows, as DWARF cannot traverse non-DWARF frames. This +would work fine, except for the fact that libgcc (our C runtime on the +MinGW platform) exports symbols under a different name when configured +to use SJLJ-style unwinding, and uses a preprocessor macro internally to +alias them. + +Because of this, we have to detect this scenario and link to the correct +symbols ourselves. Linking has been tested with a full bootstrap on both +x86_64-unknown-linux-gnu and i686-pc-windows-gnu, as well as +cross-compilation of some of my own projects. + +Obviously, the detection is a bit unrefined. Right now we +unconditionally use SJLJ when compiling Linux -> MinGW. I'd like to add +feature detection using compiler build flags or autotools-style +compilation and object analysis. Input on the best way to proceed here +is welcome. + +Also, currently there is copy-pasted/duplicated code in libunwind. +Ideally, this could be reduced, but this would likely require a +rethinking of how iOS is special-cased above, to avoid further +duplication. Input on how to best structure this file is requested. + +diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs +index c85b04ddc0..2f58f0d9fa 100644 +--- a/src/bootstrap/compile.rs ++++ b/src/bootstrap/compile.rs +@@ -145,6 +145,11 @@ pub fn std_cargo(build: &Build, + cargo.env("MACOSX_DEPLOYMENT_TARGET", target); + } + ++ // FIXME: Temporary detection of SJLJ MinGW compilers. ++ if build.build.contains("linux") && target == "i686-pc-windows-gnu" { ++ features.push_str(" sjlj_eh"); ++ } ++ + // When doing a local rebuild we tell cargo that we're stage1 rather than + // stage0. This works fine if the local rust and being-built rust have the + // same view of what the default allocator is, but fails otherwise. Since +diff --git a/src/libstd/Cargo.toml b/src/libstd/Cargo.toml +index c1fe4a89d6..6c8cb330d8 100644 +--- a/src/libstd/Cargo.toml ++++ b/src/libstd/Cargo.toml +@@ -49,3 +49,4 @@ force_alloc_system = [] + panic-unwind = ["panic_unwind"] + profiler = ["profiler_builtins"] + wasm_syscall = [] ++sjlj_eh = ["unwind/sjlj_eh"] +diff --git a/src/libunwind/Cargo.toml b/src/libunwind/Cargo.toml +index fbd9789d2f..5e319c67fa 100644 +--- a/src/libunwind/Cargo.toml ++++ b/src/libunwind/Cargo.toml +@@ -14,3 +14,6 @@ doc = false + [dependencies] + core = { path = "../libcore" } + libc = { path = "../rustc/libc_shim" } ++ ++[features] ++sjlj_eh = [] +diff --git a/src/libunwind/libunwind.rs b/src/libunwind/libunwind.rs +index e6fff7963f..6a57cf7c93 100644 +--- a/src/libunwind/libunwind.rs ++++ b/src/libunwind/libunwind.rs +@@ -10,11 +10,6 @@ + + #![allow(bad_style)] + +-macro_rules! cfg_if { +- ( $( if #[cfg( $meta:meta )] { $($it1:item)* } else { $($it2:item)* } )* ) => +- ( $( $( #[cfg($meta)] $it1)* $( #[cfg(not($meta))] $it2)* )* ) +-} +- + use libc::{c_int, c_void, uintptr_t}; + + #[repr(C)] +@@ -84,7 +79,6 @@ pub type _Unwind_Exception_Cleanup_Fn = extern "C" fn(unwind_code: _Unwind_Reaso + exception: *mut _Unwind_Exception); + extern "C" { + #[unwind] +- pub fn _Unwind_Resume(exception: *mut _Unwind_Exception) -> !; + pub fn _Unwind_DeleteException(exception: *mut _Unwind_Exception); + pub fn _Unwind_GetLanguageSpecificData(ctx: *mut _Unwind_Context) -> *mut c_void; + pub fn _Unwind_GetRegionStart(ctx: *mut _Unwind_Context) -> _Unwind_Ptr; +@@ -216,26 +210,49 @@ if #[cfg(all(any(target_os = "ios", not(target_arch = "arm"))))] { + pc + } + } ++} // cfg_if! + +-if #[cfg(not(all(target_os = "ios", target_arch = "arm")))] { +- // Not 32-bit iOS ++cfg_if! { ++if #[cfg(all(target_os = "ios", target_arch = "arm"))] { ++ // 32-bit iOS uses SjLj and does not provide _Unwind_Backtrace() + extern "C" { + #[unwind] +- pub fn _Unwind_RaiseException(exception: *mut _Unwind_Exception) -> _Unwind_Reason_Code; +- pub fn _Unwind_Backtrace(trace: _Unwind_Trace_Fn, +- trace_argument: *mut c_void) +- -> _Unwind_Reason_Code; ++ pub fn _Unwind_Resume(exception: *mut _Unwind_Exception) -> !; ++ pub fn _Unwind_SjLj_RaiseException(e: *mut _Unwind_Exception) -> _Unwind_Reason_Code; + } +-} else { +- // 32-bit iOS uses SjLj and does not provide _Unwind_Backtrace() ++ ++ #[inline] ++ pub unsafe fn _Unwind_RaiseException(exc: *mut _Unwind_Exception) -> _Unwind_Reason_Code { ++ _Unwind_SjLj_RaiseException(exc) ++ } ++ ++} else if #[cfg(feature = "sjlj_eh")] { + extern "C" { + #[unwind] ++ pub fn _Unwind_SjLj_Resume(e: *mut _Unwind_Exception) -> !; + pub fn _Unwind_SjLj_RaiseException(e: *mut _Unwind_Exception) -> _Unwind_Reason_Code; ++ pub fn _Unwind_Backtrace(trace: _Unwind_Trace_Fn, ++ trace_argument: *mut c_void) ++ -> _Unwind_Reason_Code; ++ } ++ ++ #[inline] ++ pub unsafe fn _Unwind_Resume(exc: *mut _Unwind_Exception) -> ! { ++ _Unwind_SjLj_Resume(exc) + } + + #[inline] + pub unsafe fn _Unwind_RaiseException(exc: *mut _Unwind_Exception) -> _Unwind_Reason_Code { + _Unwind_SjLj_RaiseException(exc) + } ++} else { ++ extern "C" { ++ #[unwind] ++ pub fn _Unwind_Resume(exception: *mut _Unwind_Exception) -> !; ++ pub fn _Unwind_RaiseException(exception: *mut _Unwind_Exception) -> _Unwind_Reason_Code; ++ pub fn _Unwind_Backtrace(trace: _Unwind_Trace_Fn, ++ trace_argument: *mut c_void) ++ -> _Unwind_Reason_Code; ++ } + } + } // cfg_if! +-- +2.17.1 +