p384 - signal: 11, SIGSEGV: invalid memory reference

[sundeep-kokkonda]

When the p384 crate compiling we are getting 'signal: 11, SIGSEGV: invalid memory reference' error. This issue is occurring on 32-bit architecture machines when doing DEBUG build.
Also, this issue is observed only when building this in Yocto. In rust tarball sources we couldn't reproduce the issue.

Below is the build command and error message.

**Build command:**
process didn't exit successfully: `rustc --crate-name p384 --edition=2021 /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/rustc-1.70.0-src/vendor/p384/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --crate-type lib --emit=dep-info,metadata,link -C embed-bitcode=no -C debuginfo=2 --cfg 'feature="arithmetic"' --cfg 'feature="default"' --cfg 'feature="digest"' --cfg 'feature="ecdh"' --cfg 'feature="ecdsa"' --cfg 'feature="ecdsa-core"' --cfg 'feature="pem"' --cfg 'feature="pkcs8"' --cfg 'feature="sha2"' --cfg 'feature="sha384"' --cfg 'feature="std"' -C metadata=d8c37f70a895ae9a -C extra-filename=-d8c37f70a895ae9a --out-dir /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/build/target/i686-poky-linux-gnu/debug/deps --target i686-poky-linux-gnu -C linker=/home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/wrapper/target-rust-ccld -L dependency=/home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/build/target/i686-poky-linux-gnu/debug/deps -L dependency=/home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/build/target/debug/deps --extern ecdsa_core=/home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/build/target/i686-poky-linux-gnu/debug/deps/libecdsa-e85642649bf0e7c9.rmeta --extern elliptic_curve=/home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/build/target/i686-poky-linux-gnu/debug/deps/libelliptic_curve-df69f4c85eaa7a64.rmeta --extern sha2=/home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/build/target/i686-poky-linux-gnu/debug/deps/libsha2-98350f9e69a514c9.rmeta --cap-lints allow -L /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot/usr/lib/rustlib/i686-poky-linux-gnu/lib --remap-path-prefix=/home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0=/usr/src/debug/cargo/1.70.0-r0` (signal: 11, SIGSEGV: invalid memory reference)

**Error:**
{"artifact":"./out-dir/p384-d8c37f70a895ae9a.d","emit":"dep-info"}
{"artifact":"./out-dir/libp384-d8c37f70a895ae9a.rmeta","emit":"metadata"}
...
...
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0xae9eb3)[0x7fcf8b8e9eb3]
| /home/work/poky/build/tmp/sysroots-uninative/x86_64-linux/lib/libc.so.6(+0x376e0)[0x7fcf8aa976e0]
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x2bff2d3)[0x7fcf8d9ff2d3]
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x1ad9d61)[0x7fcf8c8d9d61]
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x1ada845)[0x7fcf8c8da845]
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x1adb402)[0x7fcf8c8db402]
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x1adb402)[0x7fcf8c8db402]
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x1adb402)[0x7fcf8c8db402]
|... <<< same above line repeated several times >>> ...
|...
|...
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x1adb402)[0x7fcf8c8db402]
| /home/work/poky/build/tmp/work/core2-32-poky-linux/cargo/1.70.0-r0/recipe-sysroot-native/usr/lib/librustc_driver-62e98be45f5bb4e6.so(+0x1adb402)[0x7fcf8c8db402]
| error: could not compile `p384` (lib)

We've tried to fix the issue and below 2 ways are fixing the linking problem for this crate but it has some side effects on rest of the build.

1. From build command when the '-C debuginfo=2' option removed the linking is success for this package. (But the other crates are getting failed by some other errors referring the functions from this crate are not found in the scope. May be disabling the debug causing some missing info?)
2. By keeping '-C debuginfo=2' and by removing the features 'arithmetic, ecdh, ecdsa & ecdsa-core' also making the package to link successfully. (Is there any way I can tell cargo to remove these features from this package and it's depending packages alone?)

Is this the issue in p384 when using debug / with these features?

[tarcieri]

This sounds like a potential bug in rustc. You probably want to report it upstream here: https://github.com/rust-lang/rust/issues