On Thu, Oct 5, 2023 at 2:41 PM Matthew Maurer <mmaurer@xxxxxxxxxx> wrote: > > Currently, rustc defaults to invoking `cc`, even if `HOSTCC` is defined, > resulting in build failures in hermetic environments where `cc` does not > exist. This includes both hostprogs and proc-macros. > > Since we are setting the linker to `HOSTCC`, we set the linker flavor to > `gcc` explicitly. The linker-flavor selects both which linker to search > for if the linker is unset, and which kind of linker flags to pass. > Without this flag, `rustc` would attempt to determine which flags to > pass based on the name of the binary passed as `HOSTCC`. `gcc` is the > name of the linker-flavor used by `rustc` for all C compilers, including > both `gcc` and `clang`. > > Signed-off-by: Matthew Maurer <mmaurer@xxxxxxxxxx> > --- > > Edited to use escsq in both Makefiles, as per Masahiro Yamada's > suggestion. That looks better; thanks Matthew! Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > > rust/Makefile | 2 ++ > scripts/Makefile.host | 2 ++ > 2 files changed, 4 insertions(+) > > diff --git a/rust/Makefile b/rust/Makefile > index 87958e864be0..2ddd821d9435 100644 > --- a/rust/Makefile > +++ b/rust/Makefile > @@ -383,6 +383,8 @@ $(obj)/exports_kernel_generated.h: $(obj)/kernel.o FORCE > quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@ > cmd_rustc_procmacro = \ > $(RUSTC_OR_CLIPPY) $(rust_common_flags) \ > + -Clinker-flavor=gcc -Clinker=$(HOSTCC) \ > + -Clink-args='$(call escsq,$(KBUILD_HOSTLDFLAGS))' \ > --emit=dep-info=$(depfile) --emit=link=$@ --extern proc_macro \ > --crate-type proc-macro \ > --crate-name $(patsubst lib%.so,%,$(notdir $@)) $< > diff --git a/scripts/Makefile.host b/scripts/Makefile.host > index 8f7f842b54f9..08d83d9db31a 100644 > --- a/scripts/Makefile.host > +++ b/scripts/Makefile.host > @@ -91,6 +91,8 @@ hostcxx_flags = -Wp,-MMD,$(depfile) \ > # current working directory, which may be not accessible in the out-of-tree > # modules case. > hostrust_flags = --out-dir $(dir $@) --emit=dep-info=$(depfile) \ > + -Clinker-flavor=gcc -Clinker=$(HOSTCC) \ > + -Clink-args='$(call escsq,$(KBUILD_HOSTLDFLAGS))' \ > $(KBUILD_HOSTRUSTFLAGS) $(HOST_EXTRARUSTFLAGS) \ > $(HOSTRUSTFLAGS_$(target-stem)) > > -- > 2.42.0.609.gbb76f46606-goog > -- Thanks, ~Nick Desaulniers
