Introduce `rustc-min-version` support function that mimics
`{gcc,clang}-min-version` ones, following commit 88b61e3bff93
("Makefile.compiler: replace cc-ifversion with compiler-specific macros").
In addition, use it in the first use case we have in the kernel (which
was done independently to minimize the changes needed for the fix).
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
---
This is based on top of the fix so that the fix remains as simple as
possible:
https://lore.kernel.org/rust-for-linux/20250210163732.281786-1-ojeda@xxxxxxxxxx/
Documentation/kbuild/makefiles.rst | 14 ++++++++++++++
arch/arm64/Makefile | 2 +-
scripts/Makefile.compiler | 4 ++++
3 files changed, 19 insertions(+), 1 deletion(-)
diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst
index d36519f194dc..2608aa32c762 100644
--- a/Documentation/kbuild/makefiles.rst
+++ b/Documentation/kbuild/makefiles.rst
@@ -670,6 +670,20 @@ cc-cross-prefix
endif
endif
+$(RUSTC) support functions
+--------------------------
+
+rustc-min-version
+ rustc-min-version tests if the value of $(CONFIG_RUSTC_VERSION) is greater
+ than or equal to the provided value and evaluates to y if so.
+
+ Example::
+
+ rustflags-$(call rustc-min-version, 108500) := -Cfoo
+
+ In this example, rustflags-y will be assigned the value -Cfoo if
+ $(CONFIG_RUSTC_VERSION) is >= 1.85.0.
+
$(LD) support functions
-----------------------
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 2b25d671365f..1d5dfcd1c13e 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -48,7 +48,7 @@ KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU) \
KBUILD_CFLAGS += $(call cc-disable-warning, psabi)
KBUILD_AFLAGS += $(compat_vdso)
-ifeq ($(call test-ge, $(CONFIG_RUSTC_VERSION), 108500),y)
+ifeq ($(call rustc-min-version, 108500),y)
KBUILD_RUSTFLAGS += --target=aarch64-unknown-none-softfloat
else
KBUILD_RUSTFLAGS += --target=aarch64-unknown-none -Ctarget-feature="-neon"
diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
index 8c1029687e2e..8956587b8547 100644
--- a/scripts/Makefile.compiler
+++ b/scripts/Makefile.compiler
@@ -67,6 +67,10 @@ gcc-min-version = $(call test-ge, $(CONFIG_GCC_VERSION), $1)
# Usage: cflags-$(call clang-min-version, 110000) += -foo
clang-min-version = $(call test-ge, $(CONFIG_CLANG_VERSION), $1)
+# rustc-min-version
+# Usage: rustc-$(call rustc-min-version, 108500) += -Cfoo
+rustc-min-version = $(call test-ge, $(CONFIG_RUSTC_VERSION), $1)
+
# ld-option
# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
--
2.48.1
