Add #[used] static to always override
#146
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madsmtm
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Also great stuff 💯 When you're ready with this we can merge |
At least when the final linker invocation is driven by `rustc`.
madsmtm
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Rebased, I think this is ready now. |
Zalathar
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…zelmann Simplify `jemalloc` setup In the past, `#[used]` had to appear in the top-level crate to have a consistent effect on the linker. This has been fixed a while ago for ELF with the introduction of the `symbols.o` file in rust-lang#95604, and more recently for Mach-O in rust-lang#133832, which means that libraries can now implement the required workarounds themselves. This allows moving these `#[used]` declarations out of our `main.rs`. Specifically, I have moved them into `tikv-jemalloc-sys` where they belong in tikv/jemallocator#109 and done the same for `mimalloc` in purpleprotocol/mimalloc_rust#146 (in case we want to experiment with switching to that one day). Test with: ```sh ./x build library src/tools/rustdoc src/tools/clippy --set rust.jemalloc=true # macOS lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b _rjem_je_zone_register (lldb) run # Should breakpoint, this means that the allocator was properly linked # Linux lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b malloc (lldb) run # Should breakpoint, inspect that the `malloc` symbol comes from the `rustc` binary and not from `libc` ``` try-job: `aarch64-gnu` try-job: `dist-aarch64-linux` try-job: `dist-x86_64-musl` try-job: `dist-x86_64-apple` try-job: `dist-aarch64-apple`
Zalathar
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…zelmann Simplify `jemalloc` setup In the past, `#[used]` had to appear in the top-level crate to have a consistent effect on the linker. This has been fixed a while ago for ELF with the introduction of the `symbols.o` file in rust-lang#95604, and more recently for Mach-O in rust-lang#133832, which means that libraries can now implement the required workarounds themselves. This allows moving these `#[used]` declarations out of our `main.rs`. Specifically, I have moved them into `tikv-jemalloc-sys` where they belong in tikv/jemallocator#109 and done the same for `mimalloc` in purpleprotocol/mimalloc_rust#146 (in case we want to experiment with switching to that one day). Test with: ```sh ./x build library src/tools/rustdoc src/tools/clippy --set rust.jemalloc=true # macOS lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b _rjem_je_zone_register (lldb) run # Should breakpoint, this means that the allocator was properly linked # Linux lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b malloc (lldb) run # Should breakpoint, inspect that the `malloc` symbol comes from the `rustc` binary and not from `libc` ``` try-job: `aarch64-gnu` try-job: `dist-aarch64-linux` try-job: `dist-x86_64-musl` try-job: `dist-x86_64-apple` try-job: `dist-aarch64-apple`
Zalathar
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…zelmann Simplify `jemalloc` setup In the past, `#[used]` had to appear in the top-level crate to have a consistent effect on the linker. This has been fixed a while ago for ELF with the introduction of the `symbols.o` file in rust-lang#95604, and more recently for Mach-O in rust-lang#133832, which means that libraries can now implement the required workarounds themselves. This allows moving these `#[used]` declarations out of our `main.rs`. Specifically, I have moved them into `tikv-jemalloc-sys` where they belong in tikv/jemallocator#109 and done the same for `mimalloc` in purpleprotocol/mimalloc_rust#146 (in case we want to experiment with switching to that one day). Test with: ```sh ./x build library src/tools/rustdoc src/tools/clippy --set rust.jemalloc=true # macOS lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b _rjem_je_zone_register (lldb) run # Should breakpoint, this means that the allocator was properly linked # Linux lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b malloc (lldb) run # Should breakpoint, inspect that the `malloc` symbol comes from the `rustc` binary and not from `libc` ``` try-job: `aarch64-gnu` try-job: `dist-aarch64-linux` try-job: `dist-x86_64-musl` try-job: `dist-x86_64-apple` try-job: `dist-aarch64-apple`
Zalathar
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…zelmann Simplify `jemalloc` setup In the past, `#[used]` had to appear in the top-level crate to have a consistent effect on the linker. This has been fixed a while ago for ELF with the introduction of the `symbols.o` file in rust-lang#95604, and more recently for Mach-O in rust-lang#133832, which means that libraries can now implement the required workarounds themselves. This allows moving these `#[used]` declarations out of our `main.rs`. Specifically, I have moved them into `tikv-jemalloc-sys` where they belong in tikv/jemallocator#109 and done the same for `mimalloc` in purpleprotocol/mimalloc_rust#146 (in case we want to experiment with switching to that one day). Test with: ```sh ./x build library src/tools/rustdoc src/tools/clippy --set rust.jemalloc=true # macOS lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b _rjem_je_zone_register (lldb) run # Should breakpoint, this means that the allocator was properly linked # Linux lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b malloc (lldb) run # Should breakpoint, inspect that the `malloc` symbol comes from the `rustc` binary and not from `libc` ``` try-job: `aarch64-gnu` try-job: `dist-aarch64-linux` try-job: `dist-x86_64-musl` try-job: `dist-x86_64-apple` try-job: `dist-aarch64-apple`
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Rollup merge of #146627 - madsmtm:jemalloc-simplify, r=jdonszelmann Simplify `jemalloc` setup In the past, `#[used]` had to appear in the top-level crate to have a consistent effect on the linker. This has been fixed a while ago for ELF with the introduction of the `symbols.o` file in #95604, and more recently for Mach-O in #133832, which means that libraries can now implement the required workarounds themselves. This allows moving these `#[used]` declarations out of our `main.rs`. Specifically, I have moved them into `tikv-jemalloc-sys` where they belong in tikv/jemallocator#109 and done the same for `mimalloc` in purpleprotocol/mimalloc_rust#146 (in case we want to experiment with switching to that one day). Test with: ```sh ./x build library src/tools/rustdoc src/tools/clippy --set rust.jemalloc=true # macOS lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b _rjem_je_zone_register (lldb) run # Should breakpoint, this means that the allocator was properly linked # Linux lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b malloc (lldb) run # Should breakpoint, inspect that the `malloc` symbol comes from the `rustc` binary and not from `libc` ``` try-job: `aarch64-gnu` try-job: `dist-aarch64-linux` try-job: `dist-x86_64-musl` try-job: `dist-x86_64-apple` try-job: `dist-aarch64-apple`
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Simplify `jemalloc` setup In the past, `#[used]` had to appear in the top-level crate to have a consistent effect on the linker. This has been fixed a while ago for ELF with the introduction of the `symbols.o` file in rust-lang/rust#95604, and more recently for Mach-O in rust-lang/rust#133832, which means that libraries can now implement the required workarounds themselves. This allows moving these `#[used]` declarations out of our `main.rs`. Specifically, I have moved them into `tikv-jemalloc-sys` where they belong in tikv/jemallocator#109 and done the same for `mimalloc` in purpleprotocol/mimalloc_rust#146 (in case we want to experiment with switching to that one day). Test with: ```sh ./x build library src/tools/rustdoc src/tools/clippy --set rust.jemalloc=true # macOS lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b _rjem_je_zone_register (lldb) run # Should breakpoint, this means that the allocator was properly linked # Linux lldb -- ./build/host/stage1/bin/rustc -vV (lldb) b malloc (lldb) run # Should breakpoint, inspect that the `malloc` symbol comes from the `rustc` binary and not from `libc` ``` try-job: `aarch64-gnu` try-job: `dist-aarch64-linux` try-job: `dist-x86_64-musl` try-job: `dist-x86_64-apple` try-job: `dist-aarch64-apple`
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At least when the linker is driven by
rustc. See the comments inlibmimalloc-sys/src/lib.rsfor details.Finally fixes #41, see https://github.com/madsmtm/test-malloc-overriding for the tests I've performed.
Builds upon #145, hence why this is marked as a draft.