From: Miguel Ojeda ojeda@kernel.org
[ Upstream commit 02dfd63afe65f7bacad543ba2b10f77083ae7929 ]
Alice reported [1] that an arm64 build failed with:
ld.lld: error: undefined symbol: __extendsfdf2 >>> referenced by core.a6f5fc5794e7b7b3-cgu.0 >>> rust/core.o:(<f32>::midpoint) in archive vmlinux.a >>> referenced by core.a6f5fc5794e7b7b3-cgu.0 >>> rust/core.o:(<f32>::midpoint) in archive vmlinux.a
ld.lld: error: undefined symbol: __truncdfsf2 >>> referenced by core.a6f5fc5794e7b7b3-cgu.0 >>> rust/core.o:(<f32>::midpoint) in archive vmlinux.a
Rust 1.80.0 or later together with `CONFIG_CC_OPTIMIZE_FOR_SIZE=y` is what triggers it.
In addition, x86_64 builds also fail the same way.
Similarly, compiling with Rust 1.82.0 (currently in nightly) makes another one appear, possibly due to the LLVM 19 upgrade there:
ld.lld: error: undefined symbol: __eqdf2 >>> referenced by core.20495ea57a9f069d-cgu.0 >>> rust/core.o:(<f64>::next_up) in archive vmlinux.a >>> referenced by core.20495ea57a9f069d-cgu.0 >>> rust/core.o:(<f64>::next_down) in archive vmlinux.a
Gary adds [1]:
Usually the fix on rustc side is to mark those functions as `#[inline]`
All of {midpoint,next_up,next_down} are indeed unstable functions not marked as inline...
Fix all those by adding those intrinsics to our usual workaround.
[ Trevor quickly submitted a fix to upstream Rust [2] that has already been merged, to be released in Rust 1.82.0 (2024-10-17). - Miguel ]
Cc: Gary Guo gary@garyguo.net Reported-by: Alice Ryhl aliceryhl@google.com Closes: https://rust-for-linux.zulipchat.com/#narrow/stream/x/topic/x/near/455637364 [1] Reviewed-by: Trevor Gross tmgross@umich.edu Tested-by: Alice Ryhl aliceryhl@google.com Tested-by: Boqun Feng boqun.feng@gmail.com Reviewed-by: Gary Guo gary@garyguo.net Link: https://github.com/rust-lang/rust/pull/128749 [2] Link: https://lore.kernel.org/r/20240806150619.192882-1-ojeda@kernel.org [ Shortened Zulip link. - Miguel ] Signed-off-by: Miguel Ojeda ojeda@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- rust/Makefile | 4 ++-- rust/compiler_builtins.rs | 3 +++ 2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/rust/Makefile b/rust/Makefile index 060ba8cfa9149..9e0939b8fa78b 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -411,8 +411,8 @@ rust-analyzer: $(if $(KBUILD_EXTMOD),$(extmod_prefix),$(objtree))/rust-project.json
redirect-intrinsics = \ - __addsf3 __eqsf2 __gesf2 __lesf2 __ltsf2 __mulsf3 __nesf2 __unordsf2 \ - __adddf3 __ledf2 __ltdf2 __muldf3 __unorddf2 \ + __addsf3 __eqsf2 __extendsfdf2 __gesf2 __lesf2 __ltsf2 __mulsf3 __nesf2 __truncdfsf2 __unordsf2 \ + __adddf3 __eqdf2 __ledf2 __ltdf2 __muldf3 __unorddf2 \ __muloti4 __multi3 \ __udivmodti4 __udivti3 __umodti3
diff --git a/rust/compiler_builtins.rs b/rust/compiler_builtins.rs index bba2922c6ef77..f14b8d7caf899 100644 --- a/rust/compiler_builtins.rs +++ b/rust/compiler_builtins.rs @@ -40,16 +40,19 @@ pub extern "C" fn $ident() { define_panicking_intrinsics!("`f32` should not be used", { __addsf3, __eqsf2, + __extendsfdf2, __gesf2, __lesf2, __ltsf2, __mulsf3, __nesf2, + __truncdfsf2, __unordsf2, });
define_panicking_intrinsics!("`f64` should not be used", { __adddf3, + __eqdf2, __ledf2, __ltdf2, __muldf3,