From: "Björn Töpel" <bjorn@kernel.org>
To: Arnaldo Carvalho de Melo <acme@redhat.com>,
Jean-Philippe Brucker <jean-philippe@linaro.org>,
linux-kernel@vger.kernel.org
Cc: "Björn Töpel" <bjorn@rivosinc.com>,
"Nathan Chancellor" <nathan@kernel.org>,
"Nick Desaulniers" <ndesaulniers@google.com>,
"Tom Rix" <trix@redhat.com>,
bpf@vger.kernel.org, "Anders Roxell" <anders.roxell@linaro.org>,
llvm@lists.linux.dev, "Jiri Olsa" <olsajiri@gmail.com>
Subject: [PATCH v2] tools/build: Add clang cross-compilation flags to feature detection
Date: Thu, 2 Nov 2023 11:32:52 +0100 [thread overview]
Message-ID: <20231102103252.247147-1-bjorn@kernel.org> (raw)
From: Björn Töpel <bjorn@rivosinc.com>
When a tool cross-build has LLVM=1 set, the clang cross-compilation
flags are not passed to the feature detection build system. This
results in the host's features are detected instead of the targets.
E.g, triggering a cross-build of bpftool:
cd tools/bpf/bpftool
make ARCH=riscv CROSS_COMPILE=riscv64-linux-gnu- LLVM=1
would report the host's, and not the target's features.
Correct the issue by passing the CLANG_CROSS_FLAGS variable to the
feature detection makefile.
Fixes: cebdb7374577 ("tools: Help cross-building with clang")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
---
tools/build/Makefile.feature | 2 +-
tools/build/feature/Makefile | 12 ++++++------
2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
index 934e2777a2db..25b009a6c05f 100644
--- a/tools/build/Makefile.feature
+++ b/tools/build/Makefile.feature
@@ -8,7 +8,7 @@ endif
feature_check = $(eval $(feature_check_code))
define feature_check_code
- feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) CC="$(CC)" CXX="$(CXX)" CFLAGS="$(EXTRA_CFLAGS) $(FEATURE_CHECK_CFLAGS-$(1))" CXXFLAGS="$(EXTRA_CXXFLAGS) $(FEATURE_CHECK_CXXFLAGS-$(1))" LDFLAGS="$(LDFLAGS) $(FEATURE_CHECK_LDFLAGS-$(1))" -C $(feature_dir) $(OUTPUT_FEATURES)test-$1.bin >/dev/null 2>/dev/null && echo 1 || echo 0)
+ feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) CC="$(CC)" CXX="$(CXX)" CFLAGS="$(EXTRA_CFLAGS) $(FEATURE_CHECK_CFLAGS-$(1))" CXXFLAGS="$(EXTRA_CXXFLAGS) $(FEATURE_CHECK_CXXFLAGS-$(1))" LDFLAGS="$(LDFLAGS) $(FEATURE_CHECK_LDFLAGS-$(1))" CLANG_CROSS_FLAGS="$(CLANG_CROSS_FLAGS)" -C $(feature_dir) $(OUTPUT_FEATURES)test-$1.bin >/dev/null 2>/dev/null && echo 1 || echo 0)
endef
feature_set = $(eval $(feature_set_code))
diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
index dad79ede4e0a..c4458345e564 100644
--- a/tools/build/feature/Makefile
+++ b/tools/build/feature/Makefile
@@ -84,12 +84,12 @@ PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
all: $(FILES)
-__BUILD = $(CC) $(CFLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.c,$(@F)) $(LDFLAGS)
+__BUILD = $(CC) $(CFLAGS) $(CLANG_CROSS_FLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.c,$(@F)) $(LDFLAGS)
BUILD = $(__BUILD) > $(@:.bin=.make.output) 2>&1
BUILD_BFD = $(BUILD) -DPACKAGE='"perf"' -lbfd -ldl
BUILD_ALL = $(BUILD) -fstack-protector-all -O2 -D_FORTIFY_SOURCE=2 -ldw -lelf -lnuma -lelf -lslang $(FLAGS_PERL_EMBED) $(FLAGS_PYTHON_EMBED) -DPACKAGE='"perf"' -lbfd -ldl -lz -llzma -lzstd -lcap
-__BUILDXX = $(CXX) $(CXXFLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.cpp,$(@F)) $(LDFLAGS)
+__BUILDXX = $(CXX) $(CXXFLAGS) $(CLANG_CROSS_FLAGS) -MD -Wall -Werror -o $@ $(patsubst %.bin,%.cpp,$(@F)) $(LDFLAGS)
BUILDXX = $(__BUILDXX) > $(@:.bin=.make.output) 2>&1
###############################
@@ -259,10 +259,10 @@ $(OUTPUT)test-reallocarray.bin:
$(BUILD)
$(OUTPUT)test-libbfd-liberty.bin:
- $(CC) $(CFLAGS) -Wall -Werror -o $@ test-libbfd.c -DPACKAGE='"perf"' $(LDFLAGS) -lbfd -ldl -liberty
+ $(CC) $(CFLAGS) $(CLANG_CROSS_FLAGS) -Wall -Werror -o $@ test-libbfd.c -DPACKAGE='"perf"' $(LDFLAGS) -lbfd -ldl -liberty
$(OUTPUT)test-libbfd-liberty-z.bin:
- $(CC) $(CFLAGS) -Wall -Werror -o $@ test-libbfd.c -DPACKAGE='"perf"' $(LDFLAGS) -lbfd -ldl -liberty -lz
+ $(CC) $(CFLAGS) $(CLANG_CROSS_FLAGS) -Wall -Werror -o $@ test-libbfd.c -DPACKAGE='"perf"' $(LDFLAGS) -lbfd -ldl -liberty -lz
$(OUTPUT)test-cplus-demangle.bin:
$(BUILD) -liberty
@@ -283,10 +283,10 @@ $(OUTPUT)test-libbabeltrace.bin:
$(BUILD) # -lbabeltrace provided by $(FEATURE_CHECK_LDFLAGS-libbabeltrace)
$(OUTPUT)test-compile-32.bin:
- $(CC) -m32 -o $@ test-compile.c
+ $(CC) $(CLANG_CROSS_FLAGS) -m32 -o $@ test-compile.c
$(OUTPUT)test-compile-x32.bin:
- $(CC) -mx32 -o $@ test-compile.c
+ $(CC) $(CLANG_CROSS_FLAGS) -mx32 -o $@ test-compile.c
$(OUTPUT)test-zlib.bin:
$(BUILD) -lz
base-commit: 21e80f3841c01aeaf32d7aee7bbc87b3db1aa0c6
--
2.40.1
next reply other threads:[~2023-11-02 10:32 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-02 10:32 Björn Töpel [this message]
2023-11-02 12:30 ` [PATCH v2] tools/build: Add clang cross-compilation flags to feature detection Jiri Olsa
2024-04-26 10:31 ` Björn Töpel
2024-04-29 17:11 ` Jean-Philippe Brucker
2024-05-02 21:07 ` Björn Töpel
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