Record with only float fields cannot be passed by-value (++) to foreign code

[JoeDralliam]

rustc reports a failure when trying to pass by value to foreign code a record with only float fields. Here is a minimal code:

#[crate_type = "lib"];
type c_struct = {
    field1: libc::c_float,
    field2: libc::c_float
};

extern mod my_lib 
{
    fn my_func(++test:c_struct);
}

rustc outputs:

rust: task failed at 'bounds check', /home/joedralliam/Languages/rust-0.3/src/rustc/middle/trans/foreign.rs:256
/usr/local/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x5d)[0x7f03029f9d6d]
/usr/local/bin/../lib/librustrt.so(+0x2f82d)[0x7f0302a0e82d]
/usr/local/bin/../lib/librustrt.so(upcall_fail+0x1d0)[0x7f03029fca50]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x22c784)[0x7f0302e6b784]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x22e760)[0x7f0302e6d760]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x22bbb7)[0x7f0302e6abb7]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x22f50d)[0x7f0302e6e50d]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x232921)[0x7f0302e71921]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(_ZN6middle5trans7foreign17trans_foreign_mod17_0cf3dd58a82af2e43_03E+0xe7)[0x7f0302e28a47]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(_ZN6middle5trans4base10trans_item17_14f6b474af3dde0d3_03E+0x532)[0x7f0302dfa392]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(_ZN6middle5trans4base9trans_mod17_da4acc16ae49a7de3_03E+0xa8)[0x7f0302e288c8]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(_ZN6middle5trans4base11trans_crate17_c2a272b11eeb27bf3_03E+0x1923)[0x7f0302e3fad3]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x5cef41)[0x7f030320df41]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x5f03b0)[0x7f030322f3b0]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(_ZN6driver6driver12compile_upto17_dab5ea4234b8b9623_03E+0x19d2)[0x7f030320c062]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(+0x5f03b0)[0x7f030322f3b0]
/usr/local/bin/../lib/librustc-73389320c1332876-0.3.so(_ZN6driver6driver13compile_input17_ae5fe8605e94d2dc3_03E+0xbb)[0x7f030320e25b]
rustc[0x4065ea]
rustc[0x40fd84]
rustc[0x40c6ee]
rustc[0x40bbb8]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(+0x4dba5)[0x7f0304704ba5]
/usr/local/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7f03029fa694]
error: internal compiler error: unexpected failure
note: the compiler hit an unexpected failure path. this is a bug
note: try running with RUST_LOG=rustc=0,::rt::backtrace to get further details and report the results to github.com/mozilla/rust/issues
rust: task failed at 'explicit failure', /home/joedralliam/Languages/rust-0.3/src/rustc/driver/rustc.rs:256
/usr/local/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x5d)[0x7f03029f9d6d]
/usr/local/bin/../lib/librustrt.so(+0x2f82d)[0x7f0302a0e82d]
/usr/local/bin/../lib/librustrt.so(upcall_fail+0x1d0)[0x7f03029fca50]
rustc[0x40b03c]
rustc[0x40fd84]
rustc[0x40f908]
/usr/local/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7f03029fa694]
rust: domain main @0xd77ec0 root task failed
rust: task failed at 'killed', /home/joedralliam/Languages/rust-0.3/src/libcore/task.rs:521
/usr/local/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x5d)[0x7f03029f9d6d]
/usr/local/bin/../lib/librustrt.so(+0x2f82d)[0x7f0302a0e82d]
/usr/local/bin/../lib/librustrt.so(upcall_fail+0x1d0)[0x7f03029fca50]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(_ZN4task5yield17_8bfde8cf2fff81633_03E+0xa6)[0x7f03046fa5e6]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(+0x637c4)[0x7f030471a7c4]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(_ZN4priv11weaken_task17_883fb01bb525f2ba3_03E+0xff)[0x7f030471a63f]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(+0x7d4b4)[0x7f03047344b4]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(+0x634d5)[0x7f030471a4d5]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(+0x625e4)[0x7f03047195e4]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(+0x6194a)[0x7f030471894a]
/usr/local/bin/../lib/libcore-d27e4777a53c3e50-0.3.so(+0x4dba5)[0x7f0304704ba5]
/usr/local/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7f03029fa694]

The compiler version is 0.3 for x86_64 linux.

[graydon]

reproduced on 2013-03-20

[graydon]

non-critical for 0.6, de-milestoning

[sanxiyn]

This does not reproduce any more. I think it is same as #5754.