From f67695c9962e5f444549b3437fb8d840ec6222c8 Mon Sep 17 00:00:00 2001 From: Elliot Berman Date: Tue, 1 Feb 2022 13:35:42 -0800 Subject: kbuild: Add environment variables for userprogs flags Allow additional arguments be passed to userprogs compilation. Reproducible clang builds need to provide a sysroot and gcc path to ensure the same toolchain is used across hosts. KCFLAGS is not currently used for any user programs compilation, so add new USERCFLAGS and USERLDFLAGS which serves similar purpose as HOSTCFLAGS/HOSTLDFLAGS. Clang might detect GCC installation on hosts which have it installed to a default location in /. With addition of these environment variables, you can specify flags such as: $ make USERCFLAGS=--sysroot=/path/to/sysroot This can also be used to specify different sysroots such as musl or bionic which may be installed on the host in paths that the compiler may not search by default. Signed-off-by: Elliot Berman Reviewed-by: Nick Desaulniers Reviewed-by: Fangrui Song Signed-off-by: Masahiro Yamada --- Makefile | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 51e142f760f7..351f043e133a 100644 --- a/Makefile +++ b/Makefile @@ -431,11 +431,12 @@ HOSTCC = gcc HOSTCXX = g++ endif -export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \ - -O2 -fomit-frame-pointer -std=gnu89 -export KBUILD_USERLDFLAGS := +KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \ + -O2 -fomit-frame-pointer -std=gnu89 +KBUILD_USERCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS) +KBUILD_USERLDFLAGS := $(USERLDFLAGS) -KBUILD_HOSTCFLAGS := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS) +KBUILD_HOSTCFLAGS := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS) KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS) KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS) @@ -530,6 +531,7 @@ export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AW export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE +export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE -- cgit