Build #97918 2018-05-01T21:52:37.069006+00:00
# rustc version
rustc 1.26.0-dev (0eb87c9bf 2018-03-16)
# docs.rs version
cratesfyi 0.5.0 (579f83b 2018-03-05)
# build log
Build failed, waiting for other jobs to finish...
Updating registry `https://github.com/rust-lang/crates.io-index`
Downloading rustfmt-nightly v0.6.1
Fresh diff v0.1.11
Fresh quick-error v1.2.1
Fresh unicode-xid v0.0.4
Fresh serde v1.0.43
Fresh term v0.4.6
Fresh itoa v0.4.1
Fresh scoped-tls v0.1.1
Fresh bitflags v1.0.3
Fresh toml v0.4.6
Fresh byteorder v1.2.2
Fresh stable_deref_trait v1.0.0
Fresh utf8-ranges v1.0.0
Fresh either v1.5.0
Fresh libc v0.2.40
Fresh lazy_static v1.0.0
Fresh humantime v1.1.1
Fresh quote v0.3.15
Fresh semver-parser v0.7.0
Fresh itertools v0.7.8
Fresh atty v0.2.10
Fresh memchr v2.0.1
Fresh rand v0.4.2
Fresh smallvec v0.6.1
Fresh cc v1.0.15
Fresh synom v0.11.3
Fresh dtoa v0.4.2
Fresh aho-corasick v0.6.4
Fresh void v1.0.2
Fresh parking_lot_core v0.2.14
Fresh syn v0.11.11
Compiling serde_json v1.0.17
Compiling unicode-segmentation v1.2.1
Fresh unreachable v1.0.0
Fresh synstructure v0.6.1
Running `rustc --crate-name serde_json .cargo/registry/src/github.com-1ecc6299db9ec823/serde_json-1.0.17/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 --cfg 'feature="default"' -C metadata=a12c3b00a0b79109 -C extra-filename=-a12c3b00a0b79109 --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --extern dtoa=/home/cratesfyi/cratesfyi/debug/deps/libdtoa-28ad8b838881bfec.rlib --extern-version dtoa=dtoa,0.4.2 --extern serde=/home/cratesfyi/cratesfyi/debug/deps/libserde-75d5b5122806390e.rlib --extern-version serde=serde,1.0.43 --extern itoa=/home/cratesfyi/cratesfyi/debug/deps/libitoa-5874885598417c4c.rlib --extern-version itoa=itoa,0.4.1 --cap-lints allow`
Running `rustc --crate-name unicode_segmentation .cargo/registry/src/github.com-1ecc6299db9ec823/unicode-segmentation-1.2.1/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 -C metadata=64b2edf235644e0c -C extra-filename=-64b2edf235644e0c --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --cap-lints allow`
Fresh failure_derive v0.1.1
Compiling rustc-ap-serialize v113.0.0
Fresh backtrace-sys v0.1.16
Running `rustc --crate-name serialize .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 -C metadata=07b919bc415a7e32 -C extra-filename=-07b919bc415a7e32 --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --cap-lints allow`
Fresh term v0.5.1
Fresh ucd-util v0.1.1
Fresh unicode-xid v0.1.0
Fresh proc-macro2 v0.3.8
Compiling quote v0.5.2
Running `rustc --crate-name quote .cargo/registry/src/github.com-1ecc6299db9ec823/quote-0.5.2/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 --cfg 'feature="proc-macro2"' --cfg 'feature="default"' --cfg 'feature="proc-macro"' -C metadata=f3c9afc7b9c6c46c -C extra-filename=-f3c9afc7b9c6c46c --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --extern proc_macro2=/home/cratesfyi/cratesfyi/debug/deps/libproc_macro2-9fc03589b7f37a50.rlib --extern-version proc_macro2=proc-macro2,0.3.8 --cap-lints allow`
Fresh thread_local v0.3.5
Fresh owning_ref v0.3.3
Fresh regex-syntax v0.5.6
Fresh termcolor v0.3.6
Fresh cfg-if v0.1.2
Fresh unicode-width v0.1.4
Compiling regex v0.2.11
Fresh semver v0.9.0
Fresh log v0.4.1
Compiling rustfmt-nightly v0.6.1
Running `rustc --crate-name regex .cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.11/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 --cfg 'feature="default"' -C metadata=1e7c3af47d940865 -C extra-filename=-1e7c3af47d940865 --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --extern aho_corasick=/home/cratesfyi/cratesfyi/debug/deps/libaho_corasick-e524697c89f1b116.rlib --extern-version aho_corasick=aho-corasick,0.6.4 --extern regex_syntax=/home/cratesfyi/cratesfyi/debug/deps/libregex_syntax-7fca30126a41c4f8.rlib --extern-version regex_syntax=regex-syntax,0.5.6 --extern thread_local=/home/cratesfyi/cratesfyi/debug/deps/libthread_local-db3ee6d3c7fe5526.rlib --extern-version thread_local=thread_local,0.3.5 --extern memchr=/home/cratesfyi/cratesfyi/debug/deps/libmemchr-f754cb82c0139373.rlib --extern-version memchr=memchr,2.0.1 --extern utf8_ranges=/home/cratesfyi/cratesfyi/debug/deps/libutf8_ranges-b81dc320c0a952bb.rlib --extern-version utf8_ranges=utf8-ranges,1.0.0 --cap-lints allow`
Fresh parking_lot v0.5.5
Compiling ena v0.9.2
Running `rustc --crate-name build_script_build .cargo/registry/src/github.com-1ecc6299db9ec823/rustfmt-nightly-0.6.1/build.rs --crate-type bin --emit=dep-info,link -C debuginfo=2 --cfg 'feature="cargo-fmt"' --cfg 'feature="default"' --cfg 'feature="rustfmt-format-diff"' -C metadata=ba0ad55b7049a7cb -C extra-filename=-ba0ad55b7049a7cb --out-dir /home/cratesfyi/cratesfyi/debug/build/rustfmt-nightly-ba0ad55b7049a7cb -L dependency=/home/cratesfyi/cratesfyi/debug/deps --cap-lints allow`
Compiling rustc-ap-rustc_cratesio_shim v113.0.0
Running `rustc --crate-name ena .cargo/registry/src/github.com-1ecc6299db9ec823/ena-0.9.2/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 -C metadata=247edaf92b1f41c1 -C extra-filename=-247edaf92b1f41c1 --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --extern log=/home/cratesfyi/cratesfyi/debug/deps/liblog-7b5222ee8547b4c8.rlib --extern-version log=log,0.4.1 --cap-lints allow`
Running `rustc --crate-name rustc_cratesio_shim .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-rustc_cratesio_shim-113.0.0/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 -C metadata=9fe4c96745c92039 -C extra-filename=-9fe4c96745c92039 --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --extern bitflags=/home/cratesfyi/cratesfyi/debug/deps/libbitflags-147fcc7260b78db4.rlib --extern-version bitflags=bitflags,1.0.3 --extern log=/home/cratesfyi/cratesfyi/debug/deps/liblog-7b5222ee8547b4c8.rlib --extern-version log=log,0.4.1 --extern term=/home/cratesfyi/cratesfyi/debug/deps/libterm-ebf2d46f2c9791bb.rlib --extern-version term=term,0.4.6 --cap-lints allow`
Fresh rustc-demangle v0.1.7
Fresh backtrace v0.3.6
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:30:32
|
30 | fn emit_u128(&mut self, v: u128) -> Result<(), Self::Error>;
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:36:32
|
36 | fn emit_i128(&mut self, v: i128) -> Result<(), Self::Error>;
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:149:39
|
149 | fn read_u128(&mut self) -> Result<u128, Self::Error>;
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:155:39
|
155 | fn read_i128(&mut self) -> Result<i128, Self::Error>;
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:335:20
|
335 | impl Encodable for u128 {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:341:20
|
341 | impl Decodable for u128 {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:342:48
|
342 | fn decode<D: Decoder>(d: &mut D) -> Result<u128, D::Error> {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:407:20
|
407 | impl Encodable for i128 {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:413:20
|
413 | impl Decodable for i128 {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/serialize.rs:414:48
|
414 | fn decode<D: Decoder>(d: &mut D) -> Result<i128, D::Error> {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
Fresh error-chain v0.11.0
Fresh failure v0.1.1
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/json.rs:497:32
|
497 | fn emit_u128(&mut self, v: u128) -> EncodeResult { emit_enquoted_if_mapkey!(self, v) }
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/json.rs:504:32
|
504 | fn emit_i128(&mut self, v: i128) -> EncodeResult { emit_enquoted_if_mapkey!(self, v) }
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/json.rs:747:32
|
747 | fn emit_u128(&mut self, v: u128) -> EncodeResult { emit_enquoted_if_mapkey!(self, v) }
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/json.rs:754:32
|
754 | fn emit_i128(&mut self, v: i128) -> EncodeResult { emit_enquoted_if_mapkey!(self, v) }
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/json.rs:2142:34
|
2142 | read_primitive! { read_u128, u128 }
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/json.rs:2148:34
|
2148 | read_primitive! { read_i128, i128 }
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
Fresh getopts v0.2.17
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:69:32
|
69 | fn emit_u128(&mut self, v: u128) -> EncodeResult {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:49:87
|
49 | let bytes_written = write_signed_leb128($enc.cursor.get_mut(), pos, $value as i128);
| ^^^^
...
98 | write_sleb128!(self, v)
| ----------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:102:32
|
102 | fn emit_i128(&mut self, v: i128) -> EncodeResult {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:49:87
|
49 | let bytes_written = write_signed_leb128($enc.cursor.get_mut(), pos, $value as i128);
| ^^^^
...
103 | write_sleb128!(self, v)
| ----------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:49:87
|
49 | let bytes_written = write_signed_leb128($enc.cursor.get_mut(), pos, $value as i128);
| ^^^^
...
108 | write_sleb128!(self, v)
| ----------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:49:87
|
49 | let bytes_written = write_signed_leb128($enc.cursor.get_mut(), pos, $value as i128);
| ^^^^
...
113 | write_sleb128!(self, v)
| ----------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:49:87
|
49 | let bytes_written = write_signed_leb128($enc.cursor.get_mut(), pos, $value as i128);
| ^^^^
...
118 | write_sleb128!(self, v)
| ----------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:238:39
|
238 | fn read_u128(&mut self) -> Result<u128, Self::Error> {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:270:39
|
270 | fn read_i128(&mut self) -> Result<i128, Self::Error> {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/opaque.rs:271:29
|
271 | read_sleb128!(self, i128)
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:36:78
|
36 | pub fn $fn_name(out: &mut Vec<u8>, start_position: usize, mut value: $int_ty) -> usize {
| ^^^^^^^
...
61 | impl_write_unsigned_leb128!(write_u128_leb128, u128);
| ----------------------------------------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:68:43
|
68 | pub fn $fn_name(slice: &[u8]) -> ($int_ty, usize) {
| ^^^^^^^
...
96 | impl_read_unsigned_leb128!(read_u128_leb128, u128);
| --------------------------------------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:69:29
|
69 | let mut result: $int_ty = 0;
| ^^^^^^^
...
96 | impl_read_unsigned_leb128!(read_u128_leb128, u128);
| --------------------------------------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:78:45
|
78 | result |= ((byte & 0x7F) as $int_ty) << shift;
| ^^^^^^^
...
96 | impl_read_unsigned_leb128!(read_u128_leb128, u128);
| --------------------------------------------------- in this macro invocation
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:108:45
|
108 | pub fn write_signed_leb128_to<W>(mut value: i128, mut write: W) -> usize
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:133:77
|
133 | pub fn write_signed_leb128(out: &mut Vec<u8>, start_position: usize, value: i128) -> usize {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:138:67
|
138 | pub fn read_signed_leb128(data: &[u8], start_position: usize) -> (i128, usize) {
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
error[E0658]: 128-bit type is unstable (see issue #35118)
--> .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/leb128.rs:147:37
|
147 | result |= ((byte & 0x7F) as i128) << shift;
| ^^^^
|
= help: add #![feature(i128_type)] to the crate attributes to enable
Running `/home/cratesfyi/cratesfyi/debug/build/rustfmt-nightly-ba0ad55b7049a7cb/build-script-build`
Compiling syn v0.13.4
Running `rustc --crate-name syn .cargo/registry/src/github.com-1ecc6299db9ec823/syn-0.13.4/src/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 --cfg 'feature="proc-macro2"' --cfg 'feature="default"' --cfg 'feature="derive"' --cfg 'feature="visit"' --cfg 'feature="printing"' --cfg 'feature="clone-impls"' --cfg 'feature="proc-macro"' --cfg 'feature="quote"' --cfg 'feature="parsing"' -C metadata=0040bb30ee37c68e -C extra-filename=-0040bb30ee37c68e --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --extern proc_macro2=/home/cratesfyi/cratesfyi/debug/deps/libproc_macro2-9fc03589b7f37a50.rlib --extern-version proc_macro2=proc-macro2,0.3.8 --extern unicode_xid=/home/cratesfyi/cratesfyi/debug/deps/libunicode_xid-3eff40339770c4d8.rlib --extern-version unicode_xid=unicode-xid,0.1.0 --extern quote=/home/cratesfyi/cratesfyi/debug/deps/libquote-f3c9afc7b9c6c46c.rlib --extern-version quote=quote,0.5.2 --cap-lints allow`
error: aborting due to 34 previous errors
For more information about this error, try `rustc --explain E0658`.
error: Could not compile `rustc-ap-serialize`.
Caused by:
process didn't exit successfully: `rustc --crate-name serialize .cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-serialize-113.0.0/lib.rs --crate-type lib --emit=dep-info,link -C debuginfo=2 -C metadata=07b919bc415a7e32 -C extra-filename=-07b919bc415a7e32 --out-dir /home/cratesfyi/cratesfyi/debug/deps -L dependency=/home/cratesfyi/cratesfyi/debug/deps --cap-lints allow` (exit code: 101)
thread 'main' panicked at 'Error(
CargoError(
build failed
),
State {
next_error: None,
backtrace: None
}
)', src/bin/cratesfyi.rs:142:13
note: Run with `RUST_BACKTRACE=1` for a backtrace.