rust/mk
Alex Crichton 91d799eab0 msvc: Implement runtime support for unwinding
Now that LLVM has been updated, the only remaining roadblock to implementing
unwinding for MSVC is to fill out the runtime support in `std::rt::unwind::seh`.
This commit does precisely that, fixing up some other bits and pieces along the
way:

* The `seh` unwinding module now uses `RaiseException` to initiate a panic.
* The `rust_try.ll` file was rewritten for MSVC (as it's quite different) and is
  located at `rust_try_msvc_64.ll`, only included on MSVC builds for now.
* The personality function for all landing pads generated by LLVM is hard-wired
  to `__C_specific_handler` instead of the standard `rust_eh_personality` lang
  item. This is required to get LLVM to emit SEH unwinding information instead
  of DWARF unwinding information. This also means that on MSVC the
  `rust_eh_personality` function is entirely unused (but is defined as it's a
  lang item).

More details about how panicking works on SEH can be found in the
`rust_try_msvc_64.ll` or `seh.rs` files, but I'm always open to adding more
comments!

A key aspect of this PR is missing, however, which is that **unwinding is still
turned off by default for MSVC**. There is a [bug in llvm][llvm-bug] which
causes optimizations to inline enough landing pads that LLVM chokes. If the
compiler is optimized at `-O1` (where inlining isn't enabled) then it can
bootstrap with unwinding enabled, but when optimized at `-O2` (inlining is
enabled) then it hits a fatal LLVM error.

[llvm-bug]: https://llvm.org/bugs/show_bug.cgi?id=23884
2015-06-25 09:33:15 -07:00
..
cfg mk: Move logic out of MSVC's 64-bit cfg makefile 2015-06-25 09:20:12 -07:00
clean.mk mk: Enable building LLVM targeting MSVC 2015-05-19 10:52:57 -07:00
crates.mk mk: Build crates with relative paths to rustc 2015-06-13 01:41:52 +02:00
ctags.mk Fix make TAGS.emacs. 2014-12-16 17:08:49 +01:00
debuggers.mk debuginfo: Create common debugger pretty printer module. 2015-05-30 20:06:08 +02:00
dist.mk mk: Don't build compiler-docs before installation. #25699 2015-05-22 13:02:52 -07:00
docs.mk diagnostics: Resurrect the Compiler Error Index. 2015-06-20 16:57:40 +10:00
grammar.mk Add a LALR grammar for Rust with testing support 2015-01-20 18:47:17 -08:00
host.mk
install.mk configure: Remove obsolete --disable-verify option 2015-04-08 12:16:47 -07:00
llvm.mk mk: Add the ability to depend on native LLVM tools 2015-05-19 10:53:04 -07:00
main.mk Bump to 1.3 2015-06-23 13:32:48 -07:00
perf.mk
platform.mk mk: Move logic out of MSVC's 64-bit cfg makefile 2015-06-25 09:20:12 -07:00
prepare.mk Replace nop hack, explain substitution reasoning 2015-06-13 17:27:12 +01:00
reconfig.mk mk: Fix reconfiguring top-level ./configure 2015-06-17 17:32:11 -07:00
rt.mk msvc: Implement runtime support for unwinding 2015-06-25 09:33:15 -07:00
rustllvm.mk mk: Fix MSVC build for rustllvm.lib 2015-05-19 10:52:57 -07:00
snap.mk
stage0.mk mk/stage0: complain instead of creating an empty file 2014-11-20 16:00:12 -05:00
target.mk mk: Fix MSVC bootstrapping itself 2015-05-27 19:36:28 -07:00
tests.mk Auto merge of #25654 - petrochenkov:encenv, r=alexcrichton 2015-06-02 02:08:17 +00:00
util.mk mk: Build crates with relative paths to rustc 2015-06-13 01:41:52 +02:00