With the `RUSTC_VERSION_TEXT` rebuild support in place, now proc macros can depend on that instead of `core.o`. This means that both the `core` and `macros` crates can be built in parallel, and that touching `core.o` does not trigger a rebuild of the proc macros. Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx> --- rust/Makefile | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/rust/Makefile b/rust/Makefile index 966743a9ee25..40c8d2c57024 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -329,9 +329,8 @@ quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@ --crate-name $(patsubst lib%.so,%,$(notdir $@)) $< # Procedural macros can only be used with the `rustc` that compiled it. -# Therefore, to get `libmacros.so` automatically recompiled when the compiler -# version changes, we add `core.o` as a dependency (even if it is not needed). -$(obj)/libmacros.so: $(src)/macros/lib.rs $(obj)/core.o FORCE +$(obj)/libmacros.so: $(src)/macros/lib.rs \ + $(wildcard $(objtree)/include/config/RUSTC_VERSION_TEXT) FORCE +$(call if_changed_dep,rustc_procmacro) quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L $@ -- 2.46.0
