compile-fail/asm-src-loc.rs fails on ARM when compiled without optimizations

[TimNN]

(Cross) compiling this test for arm-unknown-linux-gnueabihf fails because the error span is missing. (Reproduced on nightly-2017-03-04)

#![feature(asm)]

fn main() {
    unsafe {
        asm!("nowayisthisavalidinstruction"); //~ ERROR instruction
    }
}

Output of rustc --target=arm-unknown-linux-gnueabihf -Copt-level=0:

error: <inline asm>:1:2: error: invalid instruction
        nowayisthisavalidinstruction
        ^


error: aborting due to previous error

Output of rustc --target=arm-unknown-linux-gnueabihf -Copt-level=1:

error: <inline asm>:1:2: error: invalid instruction
        nowayisthisavalidinstruction
        ^

 --> asmt.rs:5:9
  |
5 |         asm!("nowayisthisavalidinstruction"); //~ ERROR instruction
  |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error

[Amanieu]

This seems to be an LLVM bug, I can reproduce the same behavior in Clang.

$ cat clang_asm.c 
int main() {
    asm("nowayisthisavalidinstruction");
    return 0;
}
$ clang -target arm-unknown-linux-gnueabihf clang_asm.c
<inline asm>:1:2: error: invalid instruction
        nowayisthisavalidinstruction
        ^
1 error generated.
$ clang -target arm-unknown-linux-gnueabihf clang_asm.c -O1
clang_asm.c:2:9: error: invalid instruction
    asm("nowayisthisavalidinstruction");
        ^
<inline asm>:1:2: note: instantiated into assembly here
        nowayisthisavalidinstruction
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

[Amanieu]

LLVM bug: https://bugs.llvm.org/show_bug.cgi?id=46060

[Amanieu]

Will be fixed by https://reviews.llvm.org/D80759