zero-length static array triggers LLVM assertion error on windows

[klutzy]

pub static A: &'static [int] = &[];

pub fn main() {
}

Assertion failed!

Program: d:\usr\rust\bin\rustc.exe
File: c:/bot/slave/nightly-win/build/src/llvm/lib/MC/WinCOFFObjectWriter.cpp, Line 224

Expression: Section->Number != -1 && "Sections with relocations must be real!"

---

Original: rustc --test empty.rs triggers LLVM assertion error on windows

$ touch empty.rs
$ rustc --test empty.rs

Assertion failed!

Program: c:\home\stone\rust-vanilla\build\i686-pc-mingw32\stage2\bin\rustc.exe
File: c:/home/stone/rust-vanilla/src/llvm/lib/MC/WinCOFFObjectWriter.cpp, Line 222

Expression: Section->Number != -1 && "Sections with relocations must be real!"

This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.

[klutzy]

Same error for make check-stage2-regex_macros.
This blocks make check on windows: cc #12745 #13439

[alexcrichton]

cc #10872

[klutzy]

Updated title and minimal example. (was: rustc --test empty.rs triggers LLVM assertion error on windows)

--test generates pub static TESTS: &'static [self::test::TestDescAndFn] = &[]; which cause error.

[klutzy]

Other example:

fn f(_a: &[int]) {
}

fn main() {
    static A: [int, ..0u] = [];
    f(A); // triggers assertion
}

This example is derived from println!("");.

[alexcrichton]

Interestingly, if you go from rustc to an object, then the assertion is triggered. If you go from rustc to IR to an object (through llc), no assertion is triggered.

Maybe we've set up LLVM incorrectly?

[klutzy]

upstream llvm bug: http://llvm.org/bugs/show_bug.cgi?id=18993