undefined reference to `__gxx_personality_v0' on Windows Vista 32bit with GCC 4.8.1

[thadguidry]

When trying to compile Rust on Windows Vista 32bit with toolchain set to:

export PATH="/c/mingw-builds/x32-4.8.1-release-win32-sjlj-rev2/mingw32/bin:/usr/local:$PATH"

I get the following error output:

$ make
cfg: build triple i686-pc-mingw32
cfg: host triples i686-pc-mingw32
cfg: target triples i686-pc-mingw32
cfg: host for i686-pc-mingw32 is i386
cfg: os for i686-pc-mingw32 is pc-mingw32
cfg: using gcc
cfg: disabling valgrind due to its unreliability on this platform
/home/Thad/rust/mk/stage0.mk:7: warning: overriding commands for target `i686-pc
-mingw32/stage0/bin/'
/home/Thad/rust/mk/stage0.mk:4: warning: ignoring old commands for target `i686-
pc-mingw32/stage0/bin/'
cfg: no pandoc found, omitting docs
cfg: no node found, omitting docs
cfg: no llnextgen found, omitting grammar-verification
cfg: no pandoc found, omitting library doc build
link: rt/i686-pc-mingw32/stage0/rustrt.dll
rt/rustrt.mingw32.def:2: Warning: path components stripped from LIBRARY, 'rt/rus
trt'
rt/i686-pc-mingw32/stage0/rust_upcall.o: In function `upcall_s_rust_personality'
:
C:/MinGW/msys/1.0/home/Thad/rust/src/rt/rust_upcall.cpp:279: undefined reference
 to `__gxx_personality_v0'
collect2.exe: error: ld returned 1 exit status
make: *** [rt/i686-pc-mingw32/stage0/rustrt.dll] Error 1

[luqmana]

That would be because the gcc you're using seems to only support sjlj method for stack frame unwinding whereas the rust runtime seems to want DWARF exceptions.

[brson]

That's right. But we're not using unwinding at all on windows, so this could be fixed with some #ifdefs and makefile options.

[thadguidry]

What are the plans to use on Windows, then for the idea of stack unwinding ?

[thestinger]

Proper exception handling on Windows still needs to be implemented in LLVM.

http://llvm.org/bugs/show_bug.cgi?id=11285

It looks like they might have gone with a half working hack for now resulting in 64-bit support on Windows being dropped.

[brson]

#908 is the windows unwinding issue. We intend to implement unwinding with a special windows-only abi that passes an 'unwind' flag (referred to as 'return-based unwinding').

[brson]

@graydon has a patch for return-unwind somewhere if somebody wants to pick it up.

[thadguidry]

Some LLVM patches exist for simple Windows 64 Exception Handling support in LLVM. See LLVMdev message http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-April/060838.html

[thadguidry]

@graydon @brson @thestinger @luqmana I found some additional info from Andrew Kaylor @ Intel that says he recently committed MCJIT to LLVM 3.4 and it can be used for Exception Handling support (and works on Windows, but however generates ELF object images). I'm wondering if this might be useful for us ? Here's the LLVMdev thread where Andrew makes mention of it https://groups.google.com/d/msg/llvm-dev/JvrxgC_OjM8/UMpDzMCQMGkJ

[thestinger]

It's not really relevant to this, it works on Windows but doesn't have any more exception handling support than the ahead-of-time compiler does.

[klutzy]

I think "undefined reference" issue is fixed by #8488, specifically by 63e53b8. @thadguidry, could you check this?

[thadguidry]

@klutzy Yeap, it's fix now.