linking against system jemalloc is not working

[fbernier]

using JEMALLOC_OVERRIDE=/usr/lib/libjemalloc_pic.a cargo build to build against jemalloc 5.2.1 fails with

   Compiling fs_extra v1.2.0
   Compiling cc v1.0.72
   Compiling libc v0.2.112
   Compiling tikv-jemalloc-sys v0.4.2+5.2.1-patched.2
   Compiling tikv-jemallocator v0.4.1
   Compiling empty-rust v0.1.0 (/home/fbernier/code/empty-rust)
error: linking with `/usr/bin/clang` failed: exit status: 1
  |
  = note: "/usr/bin/clang" "-m64" "/home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o" "/home/fbernier/code/empty-rust/ta
4-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-4fc3313c8ccb1ec0.rlib" "/home/fbernier/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustli
b/x86_64-unknown-linux-gnu/lib/libcfg_if-19bf8dffe82b09d4.rlib" "/home/fbernier/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib
/liblibc-afc95b1640c4beca.rlib" "/home/fbernier/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-aff6658baa87e3d1.rlib"
 "/home/fbernier/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-8be8a1689a4f7b48.rlib" "/home/fber
nier/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-5284934f66073844.rlib" "-Wl,--end-group" "/home/fbernier/.rustup/t
oolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-2a0b2a4f96acb821.rlib" "-Wl,-Bdynamic" "-lc" "-lm" "-lrt" "-lpthrea
d" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-Wl,--eh-frame-hdr" "-Wl,-znoexecstack" "-L" "/home/fbernier/.rustup/toolchains/stable-x86_64-unknown-linux-gn
u/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "/home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-
Wl,-znow" "-nodefaultlibs" "--ld-path=/usr/bin/mold"
  = note: mold: error: undefined symbol: /home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o: _rjem_mallocx
          mold: error: undefined symbol: /home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o: _rjem_calloc
          mold: error: undefined symbol: /home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o: _rjem_mallocx
          mold: error: undefined symbol: /home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o: _rjem_malloc
          mold: error: undefined symbol: /home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o: _rjem_sdallocx
          mold: error: undefined symbol: /home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o: _rjem_realloc
          mold: error: undefined symbol: /home/fbernier/code/empty-rust/target/debug/deps/empty_rust-617320318ce0467b.133ezxkakzrmpn1z.rcgu.o: _rjem_rallocx
          clang-13: error: linker command failed with exit code 1 (use -v to see invocation)

This is with mold but it's the same with other linkers. Building with the original jemallocator instead does work.

[BusyJay]

You may wish to check if libjemalloc_pic.a is compiled with the same prefix as tikv-jemalloc-sys, which is use _rjem_ by default. By enabling unprefixed_malloc_on_supported_platforms feature, prefix can be removed completely on Linux and other supported platforms.

[fbernier]

Indeed, the jemalloc that ships with debian and arch linux is not prefixed, and using CARGO_FEATURE_UNPREFIXED_MALLOC_ON_SUPPORTED_PLATFORMS=1 compiles properly.

Thanks!