diff mbox series

[v4,1/4] kbuild: rust: Define probing macros for rustc

Message ID 20240820194910.187826-2-mmaurer@google.com (mailing list archive)
State New
Headers show
Series Rust KASAN Support | expand

Commit Message

Matthew Maurer Aug. 20, 2024, 7:48 p.m. UTC 
Creates flag probe macro variants for `rustc`. These are helpful
because:

1. The kernel now supports a minimum `rustc` version rather than a
   single version.
2. `rustc` links against a range of LLVM revisions, occasionally even
   ones without an official release number. Since the availability of
   some Rust flags depends on which LLVM it has been linked against,
   probing is necessary.

Signed-off-by: Matthew Maurer <mmaurer@google.com>
---
 scripts/Kconfig.include   |  8 ++++++++
 scripts/Makefile.compiler | 15 +++++++++++++++
 2 files changed, 23 insertions(+)
diff mbox series

Patch

diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include
index 3ee8ecfb8c04..bdb187af45fd 100644
--- a/scripts/Kconfig.include
+++ b/scripts/Kconfig.include
@@ -63,3 +63,11 @@  ld-version := $(shell,set -- $(ld-info) && echo $2)
 cc-option-bit = $(if-success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null,$(1))
 m32-flag := $(cc-option-bit,-m32)
 m64-flag := $(cc-option-bit,-m64)
+
+# $(rustc-option,<flag>)
+# Return y if the Rust compiler supports <flag>, n otherwise
+# Calls to this should be guarded so that they are not evaluated if
+# CONFIG_RUST_IS_AVAILABLE is not set.
+# If you are testing for unstable features, consider testing RUSTC_VERSION
+# instead, as features may have different completeness while available.
+rustc-option = $(success,trap "rm -rf .tmp_$$" EXIT; mkdir .tmp_$$; $(RUSTC) $(1) --crate-type=rlib /dev/null --out-dir=.tmp_$$ -o .tmp_$$/tmp.rlib)
diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
index 92be0c9a13ee..057305eae85c 100644
--- a/scripts/Makefile.compiler
+++ b/scripts/Makefile.compiler
@@ -72,3 +72,18 @@  clang-min-version = $(call test-ge, $(CONFIG_CLANG_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))
+
+# __rustc-option
+# Usage: MY_RUSTFLAGS += $(call __rustc-option,$(RUSTC),$(MY_RUSTFLAGS),-Cinstrument-coverage,-Zinstrument-coverage)
+__rustc-option = $(call try-run,\
+	$(1) $(2) $(3) --crate-type=rlib /dev/null --out-dir=$$TMPOUT -o "$$TMP",$(3),$(4))
+
+# rustc-option
+# Usage: rustflags-y += $(call rustc-option,-Cinstrument-coverage,-Zinstrument-coverage)
+rustc-option = $(call __rustc-option, $(RUSTC),\
+	$(KBUILD_RUSTFLAGS),$(1),$(2))
+
+# rustc-option-yn
+# Usage: flag := $(call rustc-option-yn,-Cinstrument-coverage)
+rustc-option-yn = $(call try-run,\
+	$(RUSTC) $(KBUILD_RUSTFLAGS) $(1) --crate-type=rlib /dev/null --out-dir=$$TMPOUT -o "$$TMP",y,n)