# Debugging

## How to debug GCC LTO

Run the command with `-v -save-temps` and then extract the `lto1` line from the output and run that under the debugger.

## How to debug stdarch tests that cannot be run locally

First, run the tests normally:

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cd build/build_sysroot/sysroot_src/library/stdarch/
STDARCH_TEST_EVERYTHING=1 CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_RUNNER="sde -future -rtm_mode full --" TARGET=x86_64-unknown-linux-gnu ../../../../../y.sh cargo test
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It will show the command it ran, something like this:

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  process didn't exit successfully: `sde -future -rtm_mode full -- /home/user/projects/rustc_codegen_gcc/build/build_sysroot/sysroot_src/library/stdarch/target/debug/deps/core_arch-fd2d75f89baae5c6` (signal: 11, SIGSEGV: invalid memory reference)
----

Then add the `-debug` flag to it:

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sde -debug -future -rtm_mode full -- /home/user/projects/rustc_codegen_gcc/build/build_sysroot/sysroot_src/library/stdarch/target/debug/deps/core_arch-fd2d75f89baae5c6
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To see the symbols in `gdb`, specify the executable in your command:

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gdb /home/user/projects/rustc_codegen_gcc/build/build_sysroot/sysroot_src/library/stdarch/target/debug/deps/core_arch-fd2d75f89baae5c6
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and then write the `gdb` command that `sde` tells you to use, something like:

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target remote :51299
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